scholarly journals Agroforestri Lahan Gambut Tanpa Bakar

2020 ◽  
Vol 6 (2) ◽  
pp. 117-128
Author(s):  
Fahruni Fahruni

Peatland agroforestry management that is commonly carried out by the community is the burnt peel system. Where peat is peeled and burned, it is then used as a planting medium. Over time, this system will reduce the land surface. But there is a different system. Through the method without combustion by adding organic material above the soil surface. So as the land surface does not decrease, it will even increase in height. This study aims to (1) determine the ecological value of land with a peel-burn system and the addition of minerals without fuel, (2) determine the effectiveness of the peatland management system. The variables observed / measured in this study were (1) the content of macro nutrients (N, P, K) from the system pattern of management of firewood peel and the management system of mineral soil addition. (2) Agroforestry patterns implemented by farmers at the study site. The results showed that the method of agroforestry without burning provides more nutrients than peeled fuel. Increased soil pH is also higher than burnt peel. This method is more environmentally friendly because the peat ecosystem is maintained and the most important thing is the height of the land surface continues to increase during the exploitation time.

2021 ◽  
Author(s):  
Sarah E. Chadburn ◽  
Eleanor J. Burke ◽  
Angela V. Gallego-Sala ◽  
Noah D. Smith ◽  
M. Syndonia Bret-Harte ◽  
...  

Abstract. Peatlands have often been neglected in Earth System Models (ESMs). Where they are included, they are usually represented via a separate, prescribed grid cell fraction that is given the physical characteristics of a peat (highly organic) soil. However, in reality soils vary on a spectrum between purely mineral soil (no organic material), and purely organic soil, typically with an organic layer of variable thickness overlying mineral soil below. They are also dynamic, with organic layer thickness and its properties changing over time. Neither the spectrum of soil types nor their dynamic nature can be captured by current ESMs. Here we present a new version of an ESM land surface scheme (Joint UK Land Environment Simulator, JULES) where soil organic matter accumulation - and thus peatland formation, degradation and stability – is integrated in the vertically-resolved soil carbon scheme. We also introduce the capacity to track soil carbon age as a function of depth in JULES, and compare this to measured peat age-depth profiles. This scheme simulates dynamic feedbacks between the soil organic material and its thermal and hydraulic characteristics. We show that draining the peatlands can lead to significant carbon loss along with soil compaction and changes in peat properties. However, negative feedbacks can lead to the potential for peatlands to rewet themselves following drainage. These ecohydrological feedbacks can also lead to peatlands maintaining themselves in climates where peat formation would not otherwise initiate in the model, i.e. displaying some degree of resilience. The new model produces similar results to the original model for mineral soils, and realistic profiles of soil organic carbon for peatlands. In particular the best performing configurations had root mean squared error (RMSE) in carbon density for peat sites of 7.7–16.7 kgC m−3 depending on climate zone, when compared against typical peat profiles based on 216 sites from a global dataset of peat cores. This error is considerably smaller than the soil carbon itself (around 30–60 kgC m−3) and reduced by 35–80 % compared with standard JULES. The RMSE at mineral soil sites is also smaller in JULES-Peat than JULES itself (reduced by ~30–50 %). Thus JULES-Peat can be used as a complete scheme that simulates both organic and mineral soils. It does not require any additional input data and introduces minimal additional variables to the model. This provides a new approach for improving the simulation of organic and peatland soils, and associated carbon-cycle feedbacks in ESMs, which other land surface models could follow.


Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 295
Author(s):  
Marina Moura Morales ◽  
Nicholas Brian Comerford ◽  
Maurel Behling ◽  
Daniel Carneiro de Abreu ◽  
Iraê Amaral Guerrini

The phosphorus (P) chemistry of biochar (BC)-amended soils is poorly understood. This statement is based on the lack of published research attempting a comprehensive characterization of biochar’s influence on P sorption. Therefore, this study addressed the kinetic limitations of these processes. This was accomplished using a fast pyrolysis biochar made from a mix of waste materials applied to a highly weathered Latossolo Vermelho distrofico (Oxisol) from São Paulo, Brazil. Standard method (batch method) was used. The sorption kinetic studies indicated that P sorption in both cases, soil (S) and soil-biochar (SBC), had a relatively fast initial reaction between 0 to 5 min. This may have happened because adding biochar to the soil decreased P sorption capacity compared to the mineral soil alone. Presumably, this is a result of: (i) Inorganic phosphorus desorbed from biochar was resorbed onto the mineral soil; (ii) charcoal particles physically covered P sorption locations on soil; or (iii) the pH increased when BC was added SBC and the soil surface became more negatively charged, thus increasing anion repulsion and decreasing P sorption.


1994 ◽  
Vol 70 (2) ◽  
pp. 151-158 ◽  
Author(s):  
R. L. Fleming ◽  
D. S. Mossa

A series of spot seeding experiments was set out on coarse-textured upland sites in northwestern Ontario to investigate how black spruce (Picea mariana [Mill.] B.S.P.) seedling establishment and growth could be improved by site selection and seedbed preparation. Virtually all germination occurred within the first growing season. Annual seedling mortality rates were greatest during the first year, then declined steadily and stabilized at low levels (<10%) after the third year. The highest fifth-year establishment ratios (seedlings/viable seed sown) were found on seedbeds derived from materials near the mineral soil/humus interface. On wetter sites (i.e., higher Soil Moisture Regimes) the best seedbeds occurred closer to the soil surface. Mean fifth year establishment ratios for the best seedbeds were 0.032 on moderately fresh to fresh sites, 0.146 on very fresh to moderately moist sites, and 0.082 on moist to very moist sites. On adjacent lowland sites, slow-growing, compact Sphagnum mosses had a mean establishment ratio of 0.179. Mean fifth-year seedling heights on upland sites ranged from 12 to 14 cm, and were not strongly correlated with site or seedbed type. Key words: direct seeding, black spruce, seedbed, seedling establishment, site type and germination


1998 ◽  
Vol 78 (3) ◽  
pp. 477-479 ◽  
Author(s):  
C. J. Westman ◽  
S. Jauhiainen

Forest soil pH in southwest Finland was measured with identical sampling and analysing methods in 1970 and 1989. The acidity of the organic humus layer increased significantly as pH values measured on water and on salt suspensions decreased between the two sampling dates. For the mineral soil layers, no unambiguous trend was found. pH values measured on salt suspension tended to be unchanged or lower, while pH on water suspension in some soil layers were even higher in 1989 than in 1970. Key words: pH, repeated sampling


2018 ◽  
Vol 48 (4) ◽  
pp. 324-332 ◽  
Author(s):  
Nicola A. Kokkonen ◽  
S. Ellen Macdonald ◽  
Ian Curran ◽  
Simon M. Landhäusser ◽  
Victor J. Lieffers

Given a seed source, the quality of available substrates is a key factor in determining the success of white spruce (Picea glauca (Moench) Voss) natural regeneration. We examined the influence of substrate and competing vegetation on survival and growth of natural regeneration of white spruce up to 4 years following harvesting in deciduous-dominated upland boreal mixedwood sites. Feather moss, thick soil surface organic layers, litter, and solid wood were poor substrates for establishment. Early successional mosses establishing on mineral soil, thin organics, and rotten wood were generally favourable microsites but were not highly available on postharvest sites. Mineral soil substrates were not as suitable as expected, likely because on a postlogged site, they are associated with unfavourable environmental characteristics (e.g., low nutrient availability, exposure). There was some evidence that survival and growth of seedlings were improved by surrounding vegetation in the first years, but heavy competing vegetation had a negative impact on older seedlings. Burial by aspen litter greatly increased seedling mortality, especially when combined with a brief period of submergence due to heavy spring snowmelt. The results provide insight into conditions under which natural regeneration could be an option for establishing white spruce following harvesting of deciduous-dominated boreal mixedwood forests.


In meteorology, Precipitation is any product of the condensation of atmospheric water vapor that falls under the gravity, the rainfall being the principal form of precipitation in India. Rainfall is the most important meteorological parameter for hydrology, as it controls the other processes such as infiltration, runoff, detention storage, and evapotranspiration. When precipitation falls over a catchment area, these processes have to be satisfied before precipitation water becomes runoff. Infiltration is the vertically downward flow of rainfall into ground/underground through percolation inside the soil surface and depends on soil-type, porosity, and permeability. Runoff is the flow of rainwater over the land surface that happens when there is an excess of precipitation over an area. Runoff is produced when the rainwater exceeds the infiltration capacity of the soil. The most important relationships for any watershed are the relationship between rainfall and runoff. This relationship depends on some factors such as characteristics of rainfall, runoff, and infiltration. Though the abovementioned factors have a major impact on the volume of runoff, a consistent correlation between rainfall-runoff enables us to increase more confidence in sufficient time for the formulation of appropriate decision making for the local authority. The present research work was undertaken to analyze the correlation between annual rainfall and annual runoff for the years 1901-2018 over Jamshedpur of East Singhbhum district, Jharkhand. Further in this study, the correlation between infiltration and annual runoff was analyzed over the same area and the same data period. Correlation between temperature and annual runoff was also found. Through the graphical analysis, it was found that the value of annual rainfall and runoff are strongly correlated.As the value of the Pearson correlation coefficient (r) is almost equal to +1 which is a nearly perfect positive correlation, signifies that both variables move in the same direction. It also signifies that the two variables being compared have a perfect positive relationship; that means these two are strongly related. Through the study, it was also found that the infiltration and runoff are largely correlated. There was practically no correlation found between the values of temperature and runoff over the years.


2017 ◽  
Vol 46 (1) ◽  
pp. 131-143 ◽  
Author(s):  
Salomon Cesar Nguemhe Fils ◽  
Mumbfu Ernestine Mimba ◽  
Jean Guy Dzana ◽  
Joachim Etouna ◽  
Patrick Valerie Mounoumeck ◽  
...  

Author(s):  
Özgün Imre

Theoretically, open source solutions are a good match with the resource scarce organization such as a young academic journal to make the publication process and the knowledge shared explicit to the participants in the system. This paper uses a case study approach to investigate how the decision to have such a system depends on a myriad of factors, and tracks how the editorial team decided to adopt an open source journal management system for their knowledge management issues. The study argues that these components should not be taken in isolation by showing how the previous decisions can become a hindrance as these components change over time. The results show that some factors, though initially thought to be unimportant, can become major forces as the journal matures, and a more holistic approach could help to side-step the problems faced.


Weed Science ◽  
1980 ◽  
Vol 28 (6) ◽  
pp. 719-722 ◽  
Author(s):  
J. J. Kells ◽  
R. L. Blevins ◽  
C. E. Rieck ◽  
W. M. Muir

Field studies were conducted to determine the effect of soil surface (upper 5 cm) pH and tillage on weed control and corn (Zea maysL.) yield using simazine [2-chloro-4,6-bis-(ethylamino)-s-triazine] as the herbicide for weed control. Soil pH, weed control, and corn yield were examined under no-tillage and conventional tillage systems with and without added lime and different rates of nitrogen. Increased soil pH significantly increased weed control as compared with added lime vs. no added lime, where the surface soil pH influenced the effectiveness of the applied simazine. Soil pH had a greater effect on weed control under no-tillage than under conventional tillage. Conventional tillage significantly (P<.01) increased weed control, yield, and soil pH over no-tillage. Additions of lime as compared to unlimed treatments resulted in significantly increased weed control (83% vs. 63%), yield (5,930 vs. 5,290 kg/ha) and soil pH (5.91 vs. 5.22). The poorest weed control was observed with no-tillage on unlimed plots. A significant tillage by linear effect of nitrogen interaction for all variables resulted from a greater decrease (P<.01) in weed control and soil pH and a greater increase in yield with increased nitrogen under no-tillage than with conventional tillage.


2019 ◽  
Vol 20 (4) ◽  
pp. 751-771 ◽  
Author(s):  
Richard Seager ◽  
Jennifer Nakamura ◽  
Mingfang Ting

AbstractMechanisms of drought onset and termination are examined across North America with a focus on the southern Plains using data from land surface models and regional and global reanalyses for 1979–2017. Continental-scale analysis of covarying patterns reveals a tight coupling between soil moisture change over time and intervening precipitation anomalies. The southern Great Plains are a geographic center of patterns of hydrologic change. Drying is induced by atmospheric wave trains that span the Pacific and North America and place northerly flow anomalies above the southern Plains. In the southern Plains winter is least likely, and fall most likely, for drought onset and spring is least likely, and fall or summer most likely, for drought termination. Southern Plains soil moisture itself, which integrates precipitation over time, has a clear relationship to tropical Pacific sea surface temperature (SST) anomalies with cold conditions favoring dry soils. Soil moisture change, however, though clearly driven by precipitation, has a weaker relation to SSTs and a strong relation to internal atmospheric variability. Little evidence is found of connection of drought onset and termination to driving by temperature anomalies. An analysis of particular drought onsets and terminations on the seasonal time scale reveals commonalities in terms of circulation and moisture transport anomalies over the southern Plains but a variety of ways in which these are connected into the large-scale atmosphere and ocean state. Some onsets are likely to be quite predictable due to forcing by cold tropical Pacific SSTs (e.g., fall 2010). Other onsets and all terminations are likely not predictable in terms of ocean conditions.


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