Effects of sediment nutrients and depth on small-scale spatial heterogeneity of submersed macrophyte communities in Lake Pleasant, Pennsylvania

2004 ◽  
Vol 61 (8) ◽  
pp. 1493-1502 ◽  
Author(s):  
R K Johnson ◽  
M L Ostrofsky
Keyword(s):  
Organic Matter ◽  
Community Structure ◽  
Spatial Heterogeneity ◽  
Environmental Gradients ◽  
Small Scale ◽  
Sediment Characteristics ◽  
Available Nitrogen ◽  
Total N ◽  
Available N ◽  
Prevailing Paradigm

Sediment concentrations of total and available nitrogen (N), phosphorus (P), and potassium (K) and organic matter from the littoral zone of Lake Pleasant, Pennsylvania, were highly variable. Only organic matter and total N were correlated with depth, however. This result suggests the existence of more complex environmental gradients than the prevailing paradigm of monotonic changes in sediment characteristics with increasing depth. The spatial heterogeneity of submersed aquatic plant communities was significantly correlated with depth, and available N and P. Canonical correspondence analysis demonstrated that these three factors explained 38% of the variance in community structure. Other sediment characteristics (available K, organic matter, and total N, P and K) were not significant by themselves, but all variables combined explained 63% of community-structure variance. Cluster analysis identified species or groups of species typical of endpoints on the depth versus nutrient axes. Myriophyllum exalbescens was typical of deep sites with relatively nutrient-rich sediments, whereas deep nutrient-poor sites were dominated by Vallisneria americana and Megalodonta beckii. Shallow nutrient-rich sites were dominated by several species of Potamogeton and Elodea canadensis, and shallow nutrient-poor sites were dominated by Heteranthera dubia and Najas flexilis. These results demonstrate the importance of sediment characteristics in determining macrophytes' community structure within lakes.

Nitrogen-mineralization potential of meadow soils

1993 ◽  
Vol 73 (1) ◽  
pp. 27-38 ◽  
Author(s):  
Régis R. Simard ◽  
Adrien N'dayegamiye
Keyword(s):  
Organic Matter ◽  
Soil Quality ◽  
N Mineralization ◽  
Mineralization Rate ◽  
Total N ◽  
Available N ◽  
Gompertz Equation ◽  
Mineralizable N ◽  
Mineralization Potential ◽  
Potential Mineralization

An understanding of the mineralization factors in contrasting cultivated soils is necessary for accurate predictions of plant-available N. The objective of this work was to determine the N-mineralization potential and mathematical models that can properly describe the dynamics of the mineralization process in 20 meadow soils from Quebec. The mineralization was monitored over 55.4 wk in a laboratory incubation at 20 °C with intermittent leaching. The cumulative mineralization curves in most soils were characterized by definite lags or a sigmoidal pattern and near-linear release with time after 20 wk. The data were best described by the Gompertz equation; first-order models were inadequate. The total amount of mineralizable N and the potential mineralization rate were very closely correlated with the total amounts of C or N (r > 0.73; P < 0.01). The clay content was also correlated with these mineralization parameters and significantly improved the prediction of the cumulative and potential N-mineralization rate estimated from the total N or C content of soils. The relationships with other soil characteristics such as soil pH and available nutrient contents were weak but significant. The results of this study suggest that textural classes be added in the correction for organic matter content to improve the precision in N-fertilizer recommendation and in soil-quality classifications based on potential mineralization rate. Key words: Soil quality, potentially mineralizable N, Gompertz equation, soil organic matter, soil texture, C, N

scholarly journals Soil Fertility and Leaf Nutrient Status of Mango Orchard Sites

2020 ◽  
Vol 29 (2) ◽  
pp. 155-163
Author(s):  
Sk Musfiq Us Salehin ◽  
Gazi Md Mohsin ◽  
Tabassum Ferdous ◽  
Jobaed Ragib Zaman ◽  
Md Jashim Uddin ◽  
...  
Keyword(s):  
Organic Matter ◽  
Mangifera Indica ◽  
Organic Matter Content ◽  
Nutrient Status ◽  
Matter Content ◽  
Silty Clay ◽  
Leaf Sample ◽  
Available Nitrogen ◽  
Total N ◽  
Nitrogen Phosphorus

Twenty soil and leaf samples from 20 orchards of mango (Mangifera indica L.) were collected from different locations of Rajshahi and Satkhira regions to evaluate soil texture, pH, organic matter, available and total nitrogen, phosphorus, potassium and sulfur of soils and the concentration of N and K in mango leaves. The pH of the soil varied from 6.3 - 7.9 and organic matter content varied from 0.72 - 3.60 per cent. The available nitrogen, phosphorus, potassium, and sulfur of the soils ranged from 190 - 510, 39 - 196, 36 - 206 and 25 - 235 mg/kg, respectively. The values of total N, P, K and S were 0.03 - 0.12, 0.022 - 0.210, 0.235 - 0.0.936 and 0.005 - 0.266 per cent, respectively. The dominant soil textural class was silty clay loam. The mean concentration of nitrogen (0.88%) and potassium (0.61%) in the leaf sample was low. The overall fertility status of the soils of Rajshahi and Satkhira regions in relation to mango cultivation is moderate. Dhaka Univ. J. Biol. Sci. 29(2): 155-163, 2020 (July)

The Effects of N and P Addition on the Soil Properties of a Eucalyptus urophylla Stand

2014 ◽  
Vol 700 ◽  
pp. 314-322
Author(s):  
Qiu Jing Li ◽  
Li Xue ◽  
Hong Yue Chen
Keyword(s):  
Organic Matter ◽  
Soil Bacteria ◽  
Eucalyptus Urophylla ◽  
N Addition ◽  
N Content ◽  
Total N ◽  
Available N ◽  
Biochemical Indices ◽  
P Addition ◽  
Total P

The effects of N and P addition on soil organic matter and nutrients, microbe and enzyme were investigated in a Eucalyptus urophylla stand to provide basis for soil management. Contents of organic matter, available P of N, P and N + P addition was significantly greater than the control, total N content of N and N+P addition was significant greater than the control, contents of total P, total K and available K of P and N + P addition was significantly greater than the control, available N content of N addition was significantly greater than the control, whereas that of P addition was significantly smaller than the control. N addition significantly increased the soil actinomyces number and urease activity, but had no significant effect on the number of soil bacteria and fungus, activities of phosphatase and catalase. Number of soil bacteria, fungus and actinomyces, activities of urease, phosphatase and catalase significantly increased after P addition, and biochemical indices except for bacteria number significantly increased after N + P addition.

scholarly journals PENGARUH PENANAMAN SENGON (Paraserianthes falcataria) TERHADAP KANDUNGAN C DAN N TANAH DI DESA RESAPOMBO, DOKO, BLITAR

2018 ◽  
Vol 12 (1) ◽  
pp. 49-59
Author(s):  
Ulyan Khalif
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Fertility ◽  
Soil Quality ◽  
Organic Matter Content ◽  
Matter Content ◽  
Total N ◽  
Available N ◽  
Soil Organic Matter Content ◽  
Organic Matter Input

Landuse change are suspected to be one responsible to soil fertility decline on Resapombo, Doko, Blitar. Efforts done by local farmers to deal with these problems are plantation of P. falcataria trough a reforestation program around 2011-2012. The benefits of the program are still need to be assessed so that this research was done (1) to compare the soil quality between P. falcataria-planted field and no P.falcataria field by the parameters of soil organic matter content and available N, (2) to study the relationship between organic matter input and soil organic matter content and available N, and (3) to identify factors affecting N availability post-P. falcatariaplantation. This research used randomized block design with 5 treatments (annual crop field, 3 and 6 years P. falcaria plantation field, agroforestry field with P. falcataria + coffee + talas plantation, and ex-P. falcataria-planted field. Soil were sampled compositely by 3 replication from 0-20 cm depth. Litter were sampled from a 0.5m2 sub-plot of each treatment. Results showed that P. falcataria plantations enhance soil fertility indicated by increased soil organic matter input to 10.6 times (monoculture) and 17.6 times (agroforestry) control, increased soil organic matter content by 1.5 times (monoculture) and 2.3 times(agroforestry) control, increased total N of 1.6 times (monoculture) and 2.4 times (agroforestry) control, increased ammonium by 1.7 times (monoculture) and 3.2 times (agroforestry) control, and increased nitrate by 2.4 times (monoculture) and 3.9 times(agroforestry) control.The increased soil N content of P. falcataria-planted field were caused by higher soil organic inputs compared to those with no P. falcataria plantation. Nitrogen availability affected by soil texture but have no relationship with soil pH. However, agroforestry fields showed higher pH, organic C, total N, and available N than monoculture P. falcataria fields. Measured soil chemical properties showed no significant change by the increase of P. falcataria age, moreover, they declined down towards control on ex-P. falcatariaplantation. This indicates that reforestation would only give a temporary soil quality enhancement.

Cogongrass (Imperata cylindrica) Invasion and Eradication: Implications for Soil Nutrient Dynamics in a Longleaf Pine Sandhill Ecosystem

2013 ◽  
Vol 6 (3) ◽  
pp. 433-443 ◽  
Author(s):  
Donald L. Hagan ◽  
Shibu Jose ◽  
Kimberly Bohn ◽  
Francisco Escobedo
Keyword(s):  
Organic Matter ◽  
Nutrient Dynamics ◽  
Longleaf Pine ◽  
Organic Matter Content ◽  
Soil Nutrient ◽  
Matter Content ◽  
Imperata Cylindrica ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Available N

AbstractWe assessed pre- and posteradication nitrogen and phosphorus dynamics in longleaf pine sandhill stands severely affected by cogongrass. Across a 7-yr posteradication (glyphosate + imazapyr) “recovery chronosequence,” which included untreated cogongrass, uninvaded reference, and treated plots, we analyzed soils for total N, potentially available P (Mehlich-1 [M1]), pH, and organic matter content. We also used resin bags to assess fluxes of plant available N and P in the soil solution. Additionally, we used litterbags to monitor the decomposition and nutrient mineralization patterns of dead rhizome and foliage tissue. Our results indicate similar total N and M1-P contents in both cogongrass-invaded and uninvaded reference plots, with levels of M1-P being lower than in cogongrass plots for 5 yr after eradication. Soil organic matter did not differ between treatments. Resin bag analyses suggest that cogongrass invasion did not affect soil nitrate availability, although a pulse of NO2+ NO3occurred in the first 3 yr after eradication. No such trends were observed for ammonium. Resin-adsorbed PO4was lowest 3 yr after eradication, and pH was highest 5 yr after eradication. Our litterbag study showed that approximately 55% of foliar biomass and 23% of rhizome tissue biomass remained 18 mo after herbicide treatment. Substantial N immobilization was observed in rhizomes for the first 12 mo, with slow mineralization occurring thereafter. Rapid P mineralization occurred, with 15.4 and 20.5% of initial P remaining after 18 mo in rhizomes and foliage, respectively. Overall, our findings indicate that cogongrass invasion has little to no effect on soil nutrient cycling processes, although some significant—but ephemeral—alterations develop after eradication.

Comparison of the macroinvertebrate communities in streams in logged and undisturbed catchments 8 years after harvesting

1991 ◽  
Vol 42 (6) ◽  
pp. 689 ◽  
Author(s):  
IO Growns ◽  
JA Davis
Keyword(s):  
Organic Matter ◽  
Community Structure ◽  
Environmental Gradients ◽  
Buffer Zone ◽  
Macroinvertebrate Communities ◽  
Chemical Parameters ◽  
Fine Particulate ◽  
Physical And Chemical Parameters ◽  
Hybrid Multidimensional Scaling ◽  
Physical And Chemical

Changes in lotic macroinvertebrate communities 8 years after logging were examined in two sets of paired catchments (Sutton and Lewin) in south-western Western Australia by using analysis of variance, classification (TWINSPAN), and ordination (semi-strong hybrid multidimensional scaling). Both paired catchments contained an undisturbed stream and a stream where clearfelling had been taken to the stream edges. The Sutton catchment also contained a stream where clearfelling had occurred but a 100 m-wide strip of vegetation had been retained as a buffer zone. Differences in richness and abundance of animals between the undisturbed and clearfelled streams in the two catchments were obscured by differences between the sites within each stream. However, ordination of the samples revealed differences in the composition of the macroinvertebrate communities between the clearfelled and undisturbed streams in both catchments. Underlying environmental gradients that separated the invertebrate communities in the clearfelled streams from those in the undisturbed streams, in ordination space, were conductivity, the amount of coarse and fine particulate organic matter, and a reduction in total nitrogen. In all, 11 macroinvertebrate taxa were found to be associated with the separation of samples from the undisturbed and clearfelled streams, this response probably being due to increases in conductivity within the clearfelled streams. Macroinvertebrate community structure in the buffered stream was different from that in the undisturbed stream but was more similar to the latter than to that in the clearfelled stream. Physical and chemical parameters of the buffered stream were also more similar to those of the undisturbed stream. These results indicated that the 100 m-wide buffer zone appeared to be effective in ameliorating any disturbance due to clearfelling.

scholarly journals Effect of nitrogen application rate on soil fungi community structure in a rice-fish mutualistic system

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Shumei Cai ◽  
Weiguang Lv ◽  
Haitao Zhu ◽  
Deshan Zhang ◽  
Zishi Fu ◽  
...  
Keyword(s):  
Community Structure ◽  
Paddy Soil ◽  
Soil Fungi ◽  
Application Rate ◽  
N Application ◽  
Total N ◽  
Available N ◽  
N Application Rate ◽  
Rice Fish ◽  
Rice Monoculture

Abstract Rice-fish mutualistic production systems rationalise the use of water and soil resources in an improved approach to sustainable food production. However, drivers of fungi community structure in paddy soil, including effects of nitrogen (N) application rate, are unclear in these systems. Here, we assessed soil fungi community and soil physicochemical responses in paddy soil to contrasting rates of N application in a rice-fish system. To clarify the mutualistic effects, the rice-fish system was compared with a standard rice monoculture under a 325.5 kg ha−1 N application rate. The results showed that N application rate affected abundance of paddy soil fungi (P < 0.05). Alpha diversity and richness of fungi were lower in the rice-fish system, but evenness increased with a decrease in N application rate, while the rate of N determined diversity of soil fungi in the rice-fish system. Dominant genera in the two systems differed, and soil physicochemical properties were more important drivers of soil fungi community structure in the rice-fish mutualistic system than in rice monoculture. Total N, available N and P regulated the abundance of dominant fungi. Our results indicate that management of soil fungi may contribute to sustainable agricultural production.

Enzyme Activities of Soils during the Reversal of Desertification

2012 ◽  
Vol 599 ◽  
pp. 865-869
Author(s):  
Jing Zhang ◽  
Pei Hou
Keyword(s):  
Alkaline Phosphatase ◽  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Enzymes ◽  
Potassium Cation ◽  
Total N ◽  
Available N ◽  
Sand Land ◽  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus

Desertification reversal is actually the change of shifting sand to more typical zonal soil. During the reversal process, soil properties has drastically changed, and assessment of these changes is essential for soil management and soil health. The activities of urease, alkaline phosphatase, invertase and catalase, soil organic matter, total nitrogen, phosphorus and potassium, available nitrogen, phosphorus and potassium, cation exchange capacity (CEC) contents of soils during reversal of desertification were investigated, and multivariate analysis was used to study the relationship between soil enzymes and soil physical-chemical properties. The results showed that urease activity, alkaline phosphatise activity and invertase activity were significantly higher from fixed sand land to semi-fixed sand land to semi mobile-sand land to mobile sand land. Soil organic matter had significant positive correlation with activities of invertase, urease and alkaline phosphatase. Soil organic matter, total N and available N were the major factors influencing activities of soil enzymes.

Small-scale spatial heterogeneity of soil organic matter fractions within an original broad-Leaved korean pine forest in Changbai mountain, China

2016 ◽  
Vol 36 (20) ◽  
Author(s):  
景莎 JING Sha ◽  
田静 TIAN Jing ◽  
M.Luke McCormack M.Luke McCormack ◽  
王晶苑 WANG Jingyuan ◽  
王秋凤 WANG Qiufeng ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Spatial Heterogeneity ◽  
Pine Forest ◽  
Changbai Mountain ◽  
Small Scale ◽  
Korean Pine ◽  
Soil Organic Matter Fractions ◽  
Korean Pine Forest ◽  
Organic Matter Fractions

scholarly journals PENGARUH PENANAMAN SENGON (Paraserianthes falcataria) TERHADAP KANDUNGAN C DAN N TANAH DI DESA RESAPOMBO, DOKO, BLITAR

2018 ◽  
Vol 12 (1) ◽  
pp. 49-59
Author(s):  
Ulyan Khalif
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Fertility ◽  
Soil Quality ◽  
Organic Matter Content ◽  
Matter Content ◽  
Total N ◽  
Available N ◽  
Soil Organic Matter Content ◽  
Organic Matter Input

Landuse change are suspected to be one responsible to soil fertility decline on Resapombo, Doko, Blitar. Efforts done by local farmers to deal with these problems are plantation of P. falcataria trough a reforestation program around 2011-2012. The benefits of the program are still need to be assessed so that this research was done (1) to compare the soil quality between P. falcataria-planted field and no P.falcataria field by the parameters of soil organic matter content and available N, (2) to study the relationship between organic matter input and soil organic matter content and available N, and (3) to identify factors affecting N availability post-P. falcatariaplantation. This research used randomized block design with 5 treatments (annual crop field, 3 and 6 years P. falcaria plantation field, agroforestry field with P. falcataria + coffee + talas plantation, and ex-P. falcataria-planted field. Soil were sampled compositely by 3 replication from 0-20 cm depth. Litter were sampled from a 0.5m2 sub-plot of each treatment. Results showed that P. falcataria plantations enhance soil fertility indicated by increased soil organic matter input to 10.6 times (monoculture) and 17.6 times (agroforestry) control, increased soil organic matter content by 1.5 times (monoculture) and 2.3 times(agroforestry) control, increased total N of 1.6 times (monoculture) and 2.4 times (agroforestry) control, increased ammonium by 1.7 times (monoculture) and 3.2 times (agroforestry) control, and increased nitrate by 2.4 times (monoculture) and 3.9 times(agroforestry) control.The increased soil N content of P. falcataria-planted field were caused by higher soil organic inputs compared to those with no P. falcataria plantation. Nitrogen availability affected by soil texture but have no relationship with soil pH. However, agroforestry fields showed higher pH, organic C, total N, and available N than monoculture P. falcataria fields. Measured soil chemical properties showed no significant change by the increase of P. falcataria age, moreover, they declined down towards control on ex-P. falcatariaplantation. This indicates that reforestation would only give a temporary soil quality enhancement.

Sign in / Sign up

Export Citation Format

Share Document