scholarly journals Soil microbial nutrient constraints along a tropical forest elevation gradient: a belowground test of a biogeochemical paradigm

2015 ◽  
Vol 12 (20) ◽  
pp. 6071-6083 ◽  
Author(s):  
A. T. Nottingham ◽  
B. L. Turner ◽  
J. Whitaker ◽  
N. J. Ostle ◽  
N. P. McNamara ◽  
...  
Keyword(s):  
Tropical Forests ◽  
Elevation Gradient ◽  
Hydrolytic Enzymes ◽  
Nutrient Status ◽  
N Availability ◽  
P Availability ◽  
Total N ◽  
Peruvian Andes ◽  
Soil Microbial ◽  
Microbial Nutrient Status

Abstract. Aboveground primary productivity is widely considered to be limited by phosphorus (P) availability in lowland tropical forests and by nitrogen (N) availability in montane tropical forests. However, the extent to which this paradigm applies to belowground processes remains unresolved. We measured indices of soil microbial nutrient status in lowland, sub-montane and montane tropical forests along a natural gradient spanning 3400 m in elevation in the Peruvian Andes. With increasing elevation there were marked increases in soil concentrations of total N, total P, and readily exchangeable P, but a decrease in N mineralization determined by in situ resin bags. Microbial carbon (C) and N increased with increasing elevation, but microbial C : N : P ratios were relatively constant, suggesting homeostasis. The activity of hydrolytic enzymes, which are rich in N, decreased with increasing elevation, while the ratio of enzymes involved in the acquisition of N and P increased with increasing elevation, further indicating an increase in the relative demand for N compared to P with increasing elevation. We conclude that soil microorganisms shift investment in nutrient acquisition from P to N between lowland and montane tropical forests, suggesting that different nutrients regulate soil microbial metabolism and the soil carbon balance in these ecosystems.

scholarly journals Soil microbial nutrient constraints along a tropical forest elevation gradient: a belowground test of a biogeochemical paradigm

2015 ◽  
Vol 12 (8) ◽  
pp. 6489-6523 ◽  
Author(s):  
A. T. Nottingham ◽  
B. L. Turner ◽  
J. Whitaker ◽  
N. Ostle ◽  
N. P. McNamara ◽  
...  
Keyword(s):  
Tropical Forests ◽  
Elevation Gradient ◽  
Hydrolytic Enzymes ◽  
Nutrient Status ◽  
N Availability ◽  
P Availability ◽  
Total N ◽  
Peruvian Andes ◽  
Soil Microbial ◽  
Microbial Nutrient Status

Abstract. Aboveground primary productivity is widely considered to be limited by phosphorus (P) availability in lowland tropical forests and by nitrogen (N) availability in montane tropical forests. However, the extent to which this paradigm applies to belowground processes remains unresolved. We measured indices of soil microbial nutrient status in lowland, sub-montane and montane tropical forests along a natural gradient spanning 3400 m in elevation in the Peruvian Andes. With increasing elevation there were marked increases in soil concentrations of total N, total P, and readily-extractable P, but a decrease in N mineralization determined by in situ resin bags. Microbial carbon (C) and N increased with increasing elevation, but microbial C:N:P ratios were relatively constant, suggesting homeostasis. The activity of hydrolytic enzymes, which are rich in N, decreased with increasing elevation, while the ratios of enzymes involved in the acquisition of N and P increased with increasing elevation, further indicating a shift in the relative demand for N and P by microbial biomass. We conclude that soil microorganisms shift investment in nutrient acquisition from P to N between lowland and montane tropical forests, suggesting that different nutrients regulate soil microbial metabolism and the soil carbon balance in these ecosystems.

Liming improves soil microbial growth, but trash blanket placement increases labile carbon and nitrogen availability in a sugarcane soil of subtropical Australia

Soil Research ◽  
2018 ◽  
Vol 56 (3) ◽  
pp. 235 ◽  
Author(s):  
X. Y. Liu ◽  
M. Rezaei Rashti ◽  
M. Esfandbod ◽  
B. Powell ◽  
C. R. Chen
Keyword(s):  
Soil Ph ◽  
Enzyme Activities ◽  
Nitrogen Availability ◽  
Microbial Community Composition ◽  
Cropping System ◽  
Hot Water ◽  
Microbial Biomass C ◽  
N Availability ◽  
Total N ◽  
Soil Microbial

Liming has been widely used to decrease soil acidity, but its effects on soil nitrogen (N) availability and microbial processes in sugarcane fields are largely unknown. Adjacent sugarcane soils at 26 months after liming (26ML), 14 months after liming (14ML) and with no lime amendment (CK) in Bundaberg, Australia, were selected to investigate the effect of liming on soil N bioavailability and microbial activity in a long-term subtropical sugarcane cropping system. Liming in both 14ML and 26ML treatments significantly increased soil pH (by 1.2–1.4 units) and exchangeable Ca2+ (>2-fold) compared with the CK treatment. The lower concentrations of hot water extractable organic carbon (C) and total N and ammonium-N in the 14ML, compared with the CK and 26ML treatments, can be attributed to the absence of trash blanket placement in the former. Enhanced microbial immobilisation due to improved soil pH by liming (14ML and 26ML treatments) led to increased soil microbial biomass C and N, particularly in the presence of a trash blanket (26 ML treatment), but decreased soil respiration and metabolic quotient indicated that acidic stress conditions were alleviated in the liming treatments. Soil pH was the main factor governing soil enzyme activities, with an overall decrease in all enzyme activities in response to liming. Overall, liming and trash blanket practices improved sugarcane soil fertility. Further study is warranted to investigate the shifts in soil microbial community composition and the diversity and abundance of N-associated functional genes in response to liming in sugarcane fields.

Nutrients in Salmonid Ecosystems: Sustaining Production and Biodiversity

2003 ◽  
Keyword(s):  
Pacific Northwest ◽  
Nutrient Release ◽  
Nutrient Status ◽  
N Availability ◽  
P Availability ◽  
Streams And Rivers ◽  
Salmon River ◽  
P Limitation ◽  
The Pacific ◽  
Simplifying Assumptions

<em>Abstract.</em>—Recent studies have shown that anadromous fish deliver ecologically significant quantities of marine-derived nitrogen (N), phosphorus (P), and organic carbon (C) to lakes, rivers, and streams of the Pacific Northwest. These marine-derived nutrients (MDN) can influence the ecological functioning of receiving streams through nutrient release and food availability. In Idaho, populations of anadromous salmon have declined dramatically with many formerly salmon-bearing streams now receiving no MDN supplementation. In order to assess how the loss of MDN may influence Idaho streams and rivers, we examined the current nutrient status of streams and rivers in Idaho with particular emphasis on the limiting role of N and P. We also generated a range of estimates of the historic and current affects of MDN on selected basins of the Salmon River, Idaho. Our analysis indicates that 25–50% of Idaho’s streams are potentially nutrient limited. Further analysis suggests that N and P limitation occurred in an approximately equal number of streams. Historic contributions of MDN to the Salmon River had varying potential to influence N and P availability, ranging from undetectable to resulting in a doubling of N availability. The level of influence depended upon location within the basin and the choices made regarding some simplifying assumptions. Finally, we discuss the effectiveness of artificial fertilization as a means of compensating for lost MDN and suggest that a spiraling approach be used to design and monitor fertilization treatments.

scholarly journals Climate Warming and Soil Carbon in Tropical Forests: Insights from an Elevation Gradient in the Peruvian Andes

BioScience ◽  
2015 ◽  
Vol 65 (9) ◽  
pp. 906-921 ◽  
Author(s):  
Andrew T. Nottingham ◽  
Jeanette Whitaker ◽  
Benjamin L. Turner ◽  
Norma Salinas ◽  
Michael Zimmermann ◽  
...  
Keyword(s):  
Soil Carbon ◽  
Tropical Forests ◽  
Climate Warming ◽  
Elevation Gradient ◽  
Peruvian Andes

Site-specific growth and nutrition of planted Piceamariana in the Ontario Clay Belt.: I. Early performance

1989 ◽  
Vol 19 (2) ◽  
pp. 162-170 ◽  
Author(s):  
A. D. Munson ◽  
V. R. Timmer
Keyword(s):  
Black Spruce ◽  
N Uptake ◽  
C:N Ratio ◽  
Nutrient Status ◽  
Dry Mass ◽  
N Availability ◽  
Total N ◽  
Early Performance ◽  
Regional Forest ◽  
Forest Humus

Piceamariana (Mill.) B.S.P. (black spruce) seedlings were outplanted in three black spruce dominated ecosystems (operational groups of the regional Forest Ecosystem Classification system) of the Clay Belt and also planted in pots of intact forest humus substrates from these sites to investigate response to site nutrient condition, to diagnose limiting nutrients, and to test the effectiveness of a bioassay relative to field results. Over two seasons, growth was consistently superior on upland Feathermoss substrates, intermediate on Alnus–Herb poor substrates, and poorest on Ledum substrates, in both field and pot experiments. The inferior performance of seedlings on lowland sites was related by plant analysis to low N uptake on sphagnum-dominated substrates. Vector analysis of shoot nutrient concentration, content, and dry mass allowed simultaneous comparison of the nutrient status of seedlings outplanted on the three sites. Lower total N and higher C:N ratio in forest humus substrates on the Alnus and Ledum sites suggested that N availability may be low. The pot experiment demonstrated close correspondence with field results in the first season, indicating that a bioassay may be most useful for assessing short-term response and diagnosing nutritional factors affecting early performance.

scholarly journals Using SPAD-meter in Nitrogen Fertilization of Rosa chinensis Jacq. var. mutabilis

HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 969D-970 ◽  
Author(s):  
Giampaolo Zanin ◽  
Paolo Sambo
Keyword(s):  
Dry Weight ◽  
Nutrient Status ◽  
Organic N ◽  
N Availability ◽  
Plant Weight ◽  
Total N ◽  
Plant Organs ◽  
Rosa Chinensis ◽  
Status Assessment ◽  
Spad Meter

Rosa chinensis Jacq. var. mutabilis plants were grown in a greenhouse to determine whether a hand-held chlorophyll meter (SPAD-meter) is suitable for the plant N status assessment. Therefore, plants were fertilized with increasing levels of N, applied through urea form as top dressing. The doses were: 0, 0.15, 0.3, 0.45, 0.6, and 0.75 g of N per liter of substrate. Periodically during the growing season, plant height and width, fresh and dry weight of different plant organs at 10, 20, and 30 weeks after planting, and their total N, plant P, and K were measured. Furthermore, six times along the growing cycle, the amount of chlorophyll in leaves was estimated using a SPAD-meter and analytically measured by chlorophyll extraction with ethanol and reading through a spectrophotometer. In the same leaves, N concentration was also determined. Treatments with 0.45–0.6 g of N per liter of substrate gave the tallest and widest plant. Plant weight and flower production were also the highest with these doses. The concentration of organic N in plant organs increased along with the N availability in the substrate, which suggests that a “luxury consumption” took place. The SPAD values showed high correlation among chlorophyll and N concentrations. Values that ranged between 35–40 seemed to mean good nutrient status. A high correlation was also found among SPAD values and some of the productive characteristics, which indicates that a SPAD-meter is a suitable tool in the dynamic fertilization of rose.

scholarly journals Physicochemical Properties and Heavy Metal Concentration in Soil of Industrial Area, Zirani, Savar, Dhaka

2015 ◽  
Vol 8 (1) ◽  
pp. 65-68 ◽  
Author(s):  
MS Rahaman ◽  
F Nessa ◽  
MM Hoque ◽  
M Rehnuma ◽  
MS Islam
Keyword(s):  
Heavy Metals ◽  
Agricultural Production ◽  
Reference Value ◽  
Nutrient Status ◽  
Heavy Metal Concentration ◽  
Industrial Area ◽  
Total N ◽  
Maximum Value ◽  
Wide Range ◽  
Recommended Level

Zirani of Savar is an important industrial area of the country which provides wide range of potentiality for economic development. The purpose of the study was to observe the nutrient status and heavy metals concentration of the soil in Zirani, Savar, Dhaka. Nine soil samples were collected and analyzed through different methods for analyzing pH, OC, N, K, P, S and the heavy metals including Zn, Cd, Cu, and Pb, were investigated using Atomic Absorption Spectroscopy (AAS) technique. The analyzed result revealed the soil surrounding the dumping site was slightly acidic which is not harmful for agricultural production. The highest value of OC was recorded 2.14% at point 3 and the lowest value was 1.92% which was found in point 2 that is greater than the reference value. Except total N concentration, the amount of available P, K, and S were greater than their recommended level. In addition the result showed that the concentration of Cu and Pb were much higher than their recommended level and the maximum value of Cu was 0.09 ppm and 0.762 ppm was the maximum concentration of Pb. and the concentration of Zn and Cd were within tolerable limit. Zn at point 3 showed higher concentration which was 3.05 ppm. The maximum value of Cd was 0.09 ppm that was found at station 1 under point 3.J. Environ. Sci. & Natural Resources, 8(1): 65-68 2015

scholarly journals Nutrient Management Programs, Nitrogen Fertilizer Practices, and Groundwater Quality in Nebraska’s Central Platte Valley (U.S.), 1989–1998

2001 ◽  
Vol 1 ◽  
pp. 750-757 ◽  
Author(s):  
Stan Daberkow ◽  
Harold Taylor ◽  
Noel Gollehon ◽  
Milt Moravek
Keyword(s):  
Irrigation Water ◽  
Fertilizer Application ◽  
Management Program ◽  
N Fertilizer ◽  
N Availability ◽  
Modest Improvement ◽  
Total N ◽  
Drinking Water Standard ◽  
Irrigation Water Use ◽  
Farmer Behavior

Given the societal concern about groundwater pollution from agricultural sources, public programs have been proposed or implemented to change farmer behavior with respect to nutrient use and management. However, few of these programs designed to change farmer behavior have been evaluated due to the lack of detailed data over an appropriate time frame. The Central Platte Natural Resources District (CPNRD) in Nebraska has identified an intensively cultivated, irrigated area with average groundwater nitrate-nitrogen (N) levels about double the EPA’s safe drinking water standard. The CPNRD implemented a joint education and regulatory N management program in the mid-1980s to reduce groundwater N. This analysis reports N use and management, yield, and groundwater nitrate trends in the CPNRD for nearly 3000 continuous-corn fields from 1989 to 1998, where producers faced limits on the timing of N fertilizer application but no limits on amounts. Groundwater nitrate levels showed modest improvement over the 10 years of this analysis, falling from the 1989–1993 average of 18.9 to 18.1 mg/l during 1994–1998. The availability of N in excess of crop needs was clearly documented by the CPNRD data and was related to optimistic yield goals, irrigation water use above expected levels, and lack of adherence to commercial fertilizer application guidelines. Over the 10-year period of this analysis, producers reported harvesting an annual average of 9729 kg/ha, 1569 kg/ha (14%) below the average yield goal. During 1989�1998, producers reported annually applying an average of 162.5 kg/ha of commercial N fertilizer, 15.7 kg/ha (10%) above the guideline level. Including the N contribution from irrigation water, the potential N contribution to the environment (total N available less estimated crop use) was estimated at 71.7 kg/ha. This is an estimate of the nitrates available for denitrification, volatilization, runoff, future soil N, and leaching to groundwater. On average, between 1989–1993 and 1994–1998, producers more closely followed CPNRD N fertilizer recommendations and increased their use of postemerge N applications � an indication of improved synchrony between N availability and crop uptake.

scholarly journals Annual Variation in Soil Enzyme Activity in a Paddy Field: Soil Temperature and Nutrient Availability Are Important for Controlling Enzyme Activities

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Takashi Kunito ◽  
Takashi Shiroma ◽  
Hitoshi Moro ◽  
Hirotaka Sumi
Keyword(s):  
Acid Phosphatase ◽  
Soil Temperature ◽  
Nutrient Availability ◽  
Paddy Field ◽  
Enzyme Activities ◽  
N Availability ◽  
Field Soil ◽  
Allocation Model ◽  
Total N ◽  
Glucosidase Activity

Annual variations in enzyme activities involved in carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) cycling and soil physicochemical properties were examined in a Japanese paddy field. All the enzyme activities determined at the field soil temperature (range, 2.2°C–28.3°C) increased exponentially with soil temperature (p<0.001). Significant negative correlations were found between Bray-2P concentration and the ratio of acid phosphatase to β-D-glucosidase activity (Spearman r = −0.631, p = 0.005) and between total N and the ratio of L-asparaginase to β-D-glucosidase activity (r = −0.612, p=0.007), suggesting that in accordance with the resource allocation model, acid phosphatase and L-asparaginase were synthesized by microorganisms depending on the temporal changes in soil P and N availability. These results suggest the significance of soil temperature in controlling in situ enzyme activities in paddy soil and also that the stoichiometry of enzyme activities associated with C, N, and P acquisition reflects the soil nutrient availability.

Preaching Conservation to Andean Pentecostal Communities: A Case of Engaging Key Stakeholders of Religious Communities in Peruvian Tropical Forests

2018 ◽  
Vol 2 (1) ◽  
pp. 1-10
Author(s):  
Oscar Gonzalez
Keyword(s):  
Nature Conservation ◽  
Tropical Forests ◽  
Environmental Stewardship ◽  
Religious Communities ◽  
Rural People ◽  
Peruvian Andes ◽  
Creation Care ◽  
The Andes ◽  
Key Stakeholders ◽  
Pentecostal Churches

In Latin America, Pentecostal churches have an important presence in local Andean communities. I explored the opinions that rural people of the Pentecostal faith in the Peruvian Andes have on nature and conservation and tested the Evangelical principle of Creation Care as an effective method to approach them and get them interested in conservation issues. I attended special meetings of rural Pentecostal churches in Huanuco, Peru, in 2012 and 2013; the congregations allowed me to share the importance of nature conservation, and Creation Care facilitated this communication. I discuss the details of one of the events where I participated as an invited speaker to talk about nature conservation. For those who wish to foster a dialogue with Pentecostals and Evangelical residents of the Andes on the rationale for environmental stewardship, I recommend becoming familiar with the principle of Creation Care and looking for its application in specific environmental problems of the region.

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