Science.gov

Sample records for plantation soil volatilizacao

  1. [Soil microfauna diversity among Cunninghamia lanceolata plantations based on pyrosequencing].

    PubMed

    Wang, Sheng-Jie; Liu, Jun-Ang; He, Yuan-Hao; Zhou, Guo-Ying; Tan, Yi-Min; Zhou, Jie-Chen

    2014-06-01

    In order to study the function of soil microfauna and its responses to environmental changes, we used metagenome analyses of the 18S rDNA gene region to identify differences in microfauna diversity and community structure among fifteen soil samples belonging to five different Cunninghamia lanceolate plantations. The plantations were located in Youxian County, Hunan Province in central China. The trees in these plantations were of different ages (3, 13, and 26 years) and belonged to different ecological successions (first, second, and third successions). The total dataset comprised 94922 high quality sequences with an average length of 436 bp. The dominant taxonomic groups across all samples were Chordata, Annelida, Arthropoda, Nematoda, Rotifera and Platyhelminthes with each accounting for 60.8%, 24.0%, 7.4%, 3.6%, 1.5% and 1.2% of the sequences, respectively. There were significant differences in ACE index and Shannon index among the five plantations. The lowest diversity of soil microfauna was in the 13-year old plantation of the first ecological succession. The correlation analysis showed that both ACE and available potassium concentration were negatively correlated to the Chaol index. However, there were no significant correlations between the Shannon, Simpson indices and the physical-chemical properties of soil. Overall, the Jaccard's similarity coefficient was less than 0.4 among samples at each site, and significant differences were found among plantations. PMID:25223021

  2. [Soil quality assessment of forest stand in different plantation esosystems].

    PubMed

    Huang, Yu; Wang, Silong; Feng, Zongwei; Gao, Hong; Wang, Qingkui; Hu, Yalin; Yan, Shaokui

    2004-12-01

    After a clear-cutting of the first generation Cunninghamia lanceolata plantation in 1982, three plantation ecosystems, pure Michelia macclurei stand (PMS), pure Chinese-fir stand (PCS) and their mixed stand, were established in spring 1983, and their effects on soil characteristics were evaluated by measuring some soil physical, chemical, microbiological and biochemical parameters. After 20 years' plantation, all test indices showed differences among different forest management models. Both PMS and MCM had a favorable effect on soil fertility maintenance. Soil quality assessment showed that some soil functions, e.g., water availability, nutrient availability, root suitability and soil quality index were all in a moderate level under the mixed and pure PMS stands, whereas in a relatively lower level under successive PCS stand. The results also showed that there existed close correlations between soil total organic C (TOC), cation exchange capacity (CEC), microbial biomass-C (Cmic) and other soil physical, chemical and biological indices. Therefore, TOC, CEC and Cmic could be used as the indicators in assessing soil quality in this study area. In addition, there were also positive correlations between soil microbial biomass-C and TOC, soil microbial biomass-N and total N, and soil microbial biomass-P and total P in the present study. PMID:15825426

  3. Soil physical properties influence "black truffle" fructification in plantations.

    PubMed

    Alonso Ponce, Rafael; Ágreda, Teresa; Águeda, Beatriz; Aldea, Jorge; Martínez-Peña, Fernando; Modrego, María Pilar

    2014-04-01

    Although the important effects of pH and carbonate content of soils on "black truffle" (Tuber melanosporum) production are well known, we poorly understand the influence of soil physical properties. This study focuses on physical soil characteristics that drive successful production of black truffles in plantations. Seventy-eight Quercus ilex ssp. ballota plantations older than 10 years were studied in the province of Teruel (eastern Spain). Soil samples were analyzed for various edaphic characteristics and to locate T. melanosporum ectomycorrhizae. The influence of cultivation practices, climatic features, and soil properties on sporocarp production was assessed using multivariate analyses. Low contents of fine earth and silt and high levels of bulk density, clay content, and water-holding capacity appear to promote fructification. Watering is also highly positive for truffle fructification. We develop and discuss a logistic model to predict the probability of truffle fructification in field sites under consideration for truffle plantation establishment. The balance between water availability and aeration plays a crucial role in achieving success in black truffle plantations. PMID:24487451

  4. Long-term tobacco plantation induces soil acidification and soil base cation loss.

    PubMed

    Zhang, Yuting; He, Xinhua; Liang, Hong; Zhao, Jian; Zhang, Yueqiang; Xu, Chen; Shi, Xiaojun

    2016-03-01

    Changes in soil exchangeable cations relative to soil acidification are less studied particularly under long-term cash crop plantation. This study investigated soil acidification in an Ali-Periudic Argosols after 10-year (2002-2012) long-term continuous tobacco plantation. Soils were respectively sampled at 1933 and 2143 sites in 2002 and 2012 (also 647 tobacco plants), from seven tobacco plantation counties in the Chongqing Municipal City, southwest China. After 10-year continuous tobacco plantation, a substantial acidification was evidenced by an average decrease of 0.20 soil pH unit with a substantial increase of soil sites toward the acidic status, especially those pH ranging from 4.5 to 5.5, whereas 1.93 kmol H(+) production ha(-1) year(-1) was mostly derived from nitrogen (N) fertilizer input and plant N uptake output. After 1 decade, an average decrease of 27.6 % total exchangeable base cations or of 0.20 pH unit occurred in all seven tobacco plantation counties. Meanwhile, for one unit pH decrease, 40.3 and 28.3 mmol base cations kg(-1) soil were consumed in 2002 and 2012, respectively. Furthermore, the aboveground tobacco biomass harvest removed 339.23 kg base cations ha(-1) year(-1) from soil, which was 7.57 times higher than the anions removal, leading to a 12.52 kmol H(+) production ha(-1) year(-1) as the main reason inducing soil acidification. Overall, our results showed that long-term tobacco plantation not only stimulated soil acidification but also decreased soil acid-buffering capacity, resulting in negative effects on sustainable soil uses. On the other hand, our results addressed the importance of a continuous monitoring of soil pH changes in tobacco plantation sites, which would enhance our understanding of soil fertility of health in this region. PMID:26566613

  5. Soil organic matter on citrus plantation in Eastern Spain

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; Pereira, Paulo; Novara, Agata; Prosdocimi, Massimo

    2015-04-01

    Citrus plantations in Eastern Spain are the main crop and Valencia region is the largest world exporter. The traditional plantation are located on flood irrigated areas and the new plantation are located on slopes were drip irrigation is the source of the wetting. It has been demonstrate that the citrus plantations contribute to high erosion rates on slopes (Cerdà et al., 2009b) as it is usual on agriculture land (Cerdà et al., 2009a), but when organic farming is present the soil erosion is much lower (Cerdà and Jurgensen, 2008; Cerdà et al., 2009; Cerdà and Jurgensen, 2011). This is a worldwide phenomenon (Wu et al., 2007; Wu et al., 2011; Xu et al., 2010; Xu et al., 2012a; Xu et al., 2012b), which are a key factor of the high erosion rates in rural areas (García Orenes et al., 2009: García Orenes et al., 20010; García Orenes et al., 2012; Haregewyn et al., 2013; Zhao et al., 2013). The key factor of the contrasted response of soils to the rain in citrus is the organic matter cover. This is why the Soil Erosion and Degradation Research Team developed a survey to determine the soil erosion rates on citrus orchards under different managements. A hundred of samples were collected in a citrus plantation on slope under conventional management (Chemical management), one on organic farming, one on traditional flood irrigated organic farming and one on traditional chemical flooding farm. The organic farming soils were treated with 10000 Kg ha-1 of manure yearly. The results show that the mean soil organic matter content was 1.24 %, 3.54%, 5,43% and 2.1% respectively, which show a clear impact of organic farming in the recovery of the soil organic matter. meanwhile the on the slopes and the flood-irrigated soils are Acknowledgements The research projects GL2008-02879/BTE, LEDDRA 243857 and PREVENTING AND REMEDIATING DEGRADATION OF SOILS IN EUROPE THROUGH LAND CARE (RECARE)FP7- ENV-2013- supported this research. References Cerdà, A., Flanagan, D.C., le Bissonnais

  6. Soil organic matter on citrus plantation in Eastern Spain

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; Pereira, Paulo; Novara, Agata; Prosdocimi, Massimo

    2015-04-01

    Citrus plantations in Eastern Spain are the main crop and Valencia region is the largest world exporter. The traditional plantation are located on flood irrigated areas and the new plantation are located on slopes were drip irrigation is the source of the wetting. It has been demonstrate that the citrus plantations contribute to high erosion rates on slopes (Cerdà et al., 2009b) as it is usual on agriculture land (Cerdà et al., 2009a), but when organic farming is present the soil erosion is much lower (Cerdà and Jurgensen, 2008; Cerdà et al., 2009; Cerdà and Jurgensen, 2011). This is a worldwide phenomenon (Wu et al., 2007; Wu et al., 2011; Xu et al., 2010; Xu et al., 2012a; Xu et al., 2012b), which are a key factor of the high erosion rates in rural areas (García Orenes et al., 2009: García Orenes et al., 20010; García Orenes et al., 2012; Haregewyn et al., 2013; Zhao et al., 2013). The key factor of the contrasted response of soils to the rain in citrus is the organic matter cover. This is why the Soil Erosion and Degradation Research Team developed a survey to determine the soil erosion rates on citrus orchards under different managements. A hundred of samples were collected in a citrus plantation on slope under conventional management (Chemical management), one on organic farming, one on traditional flood irrigated organic farming and one on traditional chemical flooding farm. The organic farming soils were treated with 10000 Kg ha-1 of manure yearly. The results show that the mean soil organic matter content was 1.24 %, 3.54%, 5,43% and 2.1% respectively, which show a clear impact of organic farming in the recovery of the soil organic matter. meanwhile the on the slopes and the flood-irrigated soils are Acknowledgements The research projects GL2008-02879/BTE, LEDDRA 243857 and PREVENTING AND REMEDIATING DEGRADATION OF SOILS IN EUROPE THROUGH LAND CARE (RECARE)FP7- ENV-2013- supported this research. References Cerdà, A., Flanagan, D.C., le Bissonnais

  7. Understory herb layer exerts strong controls on soil microbial communities in subtropical plantations

    PubMed Central

    Yin, Kai; Zhang, Lei; Chen, Dima; Tian, Yichen; Zhang, Feifei; Wen, Meiping; Yuan, Chao

    2016-01-01

    The patterns and drivers of soil microbial communities in forest plantations remain inadequate although they have been extensively studied in natural forest and grassland ecosystems. In this study, using data from 12 subtropical plantation sites, we found that the overstory tree biomass and tree cover increased with increasing plantation age. However, there was a decline in the aboveground biomass and species richness of the understory herbs as plantation age increased. Biomass of all microbial community groups (i.e. fungi, bacteria, arbuscular mycorrhizal fungi, and actinomycete) decreased with increasing plantation age; however, the biomass ratio of fungi to bacteria did not change with increasing plantation age. Variation in most microbial community groups was mainly explained by the understory herb (i.e. herb biomass and herb species richness) and overstory trees (i.e. tree biomass and tree cover), while soils (i.e. soil moisture, soil organic carbon, and soil pH) explained a relative low percentage of the variation. Our results demonstrate that the understory herb layer exerts strong controls on soil microbial community in subtropical plantations. These findings suggest that maintenance of plantation health may need to consider the management of understory herb in order to increase the potential of plantation ecosystems as fast-response carbon sinks. PMID:27243577

  8. Understory herb layer exerts strong controls on soil microbial communities in subtropical plantations.

    PubMed

    Yin, Kai; Zhang, Lei; Chen, Dima; Tian, Yichen; Zhang, Feifei; Wen, Meiping; Yuan, Chao

    2016-01-01

    The patterns and drivers of soil microbial communities in forest plantations remain inadequate although they have been extensively studied in natural forest and grassland ecosystems. In this study, using data from 12 subtropical plantation sites, we found that the overstory tree biomass and tree cover increased with increasing plantation age. However, there was a decline in the aboveground biomass and species richness of the understory herbs as plantation age increased. Biomass of all microbial community groups (i.e. fungi, bacteria, arbuscular mycorrhizal fungi, and actinomycete) decreased with increasing plantation age; however, the biomass ratio of fungi to bacteria did not change with increasing plantation age. Variation in most microbial community groups was mainly explained by the understory herb (i.e. herb biomass and herb species richness) and overstory trees (i.e. tree biomass and tree cover), while soils (i.e. soil moisture, soil organic carbon, and soil pH) explained a relative low percentage of the variation. Our results demonstrate that the understory herb layer exerts strong controls on soil microbial community in subtropical plantations. These findings suggest that maintenance of plantation health may need to consider the management of understory herb in order to increase the potential of plantation ecosystems as fast-response carbon sinks. PMID:27243577

  9. Soil Erosion Protection Potential of Young Paulownia Plantation

    NASA Astrophysics Data System (ADS)

    Stepchich, Avgusta; Djodjov, Christo

    2014-05-01

    Soil erosion is removal of soil and rock particles by water, wind, ice and gravity. It is widely recognized as a global soil threat. Soils impacted by different forms of erosion cover large areas around the world. While landscape, soil and climate conditions trigger soil erosion processes, the vegetation cover reduces the soil erosion risk. About 60 % of the area of agricultural land in Bulgaria is under erosion risk, which necessitates implementation of series of measures for soil erosion control. The aim of this study is to determine the erosion protection potential and the loss of soil nutrients of young Paulownia plantation. Field experiments have been set up under unirrigated conditions at the experimental field for soil erosion studies of the N. Poushkarov Institute of Soil Science, Agrotechnology and Plant Protection near Suhodol. The local soils are Chromic Luvisols, moderately eroded. The altitude is 750 m and the slope gradient is 80. The experiment consists of four field plots for soil erosion studies, three of which planted with Paulownia Bellissima and a reference one with bare soil. The plants have been planted at a distance of 2 m between adjacent rows and 1 m between each two plants within the row. The size of each field plot is 32 m2 (4 m width and 8 m length). The plots are equipped with containers for collecting the surface runoff caused by erosive rainfall events. Biometrics, including the root-striking of the plants, their growth in height, foliage cover (projection) and stem diameter, was studied from May 13th to October 21st. The data reported cover the results from the studies during the first vegetation period after planting in the Spring of 2013. During the year four erosive rainfalls were observed with a total amount of 79.2 mm, resulting to a total amount of soil loss of 772 kg/ha from a planted plot and 551 kg/ha from bear soil. The total surface runoff is 156.7 m3/ha from planted plot and 153.1 m3/ha from bare soil. The total losses of

  10. Potential N2O emissions from leguminous tree plantation soils in the humid tropics

    NASA Astrophysics Data System (ADS)

    Arai, Seiko; Ishizuka, Shigehiro; Ohta, Seiichi; Ansori, Saifuddin; Tokuchi, Naoko; Tanaka, Nagaharu; Hardjono, Arisman

    2008-06-01

    We compared nitrous oxide (N2O) emissions over 1 year from soils of plantations growing acacia, which is a leguminous plant capable of symbiotic nitrogen fixation in root nodules, and secondary forests in Sumatra, Indonesia. N2O emissions from acacia plantation soils fluctuated seasonally, from high in the wetter season to low in the drier season, whereas N2O emissions from secondary forest soils were low throughout the year. Water-filled-pore-space data showed that denitrification contributed substantially to N2O emissions from soils at acacia sites. The average annual N2O flux in acacia plantations was 2.56 kg N ha-1 a-1, which was eight times higher than that from secondary forest soils (0.33 kg N ha-1 a-1). In secondary forests, NH4+ was the dominant form of inorganic nitrogen. However, in acacia plantations, the NH4+: NO3- ratio was relatively lower than that in secondary forests. These results suggest that secondary forests were nitrogen limited, but acacia plantations were less nitrogen limited. Leguminous tree plantations may increase nitrogen cycling, resulting in greater N2O emissions from the soil. However, on a global warming potential basis, N2O emissions from acacia plantation soils accounted for less than 10% of the carbon uptake by plants. Nevertheless, because of the spread of leguminous tree plantations in Asia, the importance of N2O emissions from leguminous tree stands will increase in the coming decades.

  11. Changes in soil quality after converting Pinus to Eucalyptus plantations in southern China

    NASA Astrophysics Data System (ADS)

    Zhang, K.; Zheng, H.; Chen, F. L.; Ouyang, Z. Y.; Wang, Y.; Wu, Y. F.; Lan, J.; Fu, M.; Xiang, X. W.

    2015-02-01

    Vegetation plays a key role in maintaining soil quality, but long-term changes in soil quality due to plant species change and successive planting are rarely reported. Using the space-for-time substitution method, adjacent plantations of Pinus and first, second, third and fourth generations of Eucalyptus in Guangxi, China were used to study changes in soil quality caused by converting Pinus to Eucalyptus and successive Eucalyptus planting. Soil chemical and biological properties were measured and a soil quality index was calculated using principal component analysis. Soil organic carbon, total nitrogen, alkaline hydrolytic nitrogen, microbial biomass carbon, microbial biomass nitrogen, cellobiosidase, phenol oxidase, peroxidase and acid phosphatase activities were significantly lower in the first and second generations of Eucalyptus plantations compared with Pinus plantation, but they were significantly higher in the third and fourth generations than in the first and second generations and significantly lower than in Pinus plantation. Soil total and available potassium were significantly lower in Eucalyptus plantations (1.8-2.5 g kg-1 and 26-66 mg kg-1) compared to the Pinus plantation (14.3 g kg-1 and 92 mg kg-1), but total phosphorus was significantly higher in Eucalyptus plantations (0.9-1.1 g kg-1) compared to the Pinus plantation (0.4 g kg-1). As an integrated indicator, soil quality index was highest in the Pinus plantation (0.92) and lowest in the first and second generations of Eucalyptus plantations (0.24 and 0.13). Soil quality index in the third and fourth generations (0.36 and 0.38) was between that in Pinus plantation and in first and second generations of Eucalyptus plantations. Changing tree species, reclamation and fertilization may have contributed to the change observed in soil quality during conversion of Pinus to Eucalyptus and successive Eucalyptus planting. Litter retention, keeping understorey coverage, and reducing soil disturbance during

  12. Soil Changes Induced by Rubber and Tea Plantation Establishment: Comparison with Tropical Rain Forest Soil in Xishuangbanna, SW China

    NASA Astrophysics Data System (ADS)

    Li, Hongmei; Ma, Youxin; Liu, Wenjie; Liu, Wenjun

    2012-11-01

    Over the past thirty years, Xishuangbanna in Southwestern China has seen dramatic changes in land use where large areas of tropical forest and fallow land have been converted to rubber and tea plantations. In this study we evaluated the effects of land use and slope on soil properties in seven common disturbed and undisturbed land-types. Results indicated that all soils were acidic, with pH values significantly higher in the 3- and 28-year-old rubber plantations. The tropical forests had the lowest bulk densities, especially significantly lower from the top 10 cm of soil, and highest soil organic matter concentrations. Soil moisture content at topsoil was highest in the mature rubber plantation. Soils in the tropical forests and abandoned cultivated land had inorganic N (IN) concentrations approximately equal in NH4 +-N and NO3 --N. However, soil IN pools were dominated by NH4 +-N in the rubber and tea plantations. This trend suggests that conversion of tropical forest to rubber and tea plantations increases NH4 +-N concentration and decreases NO3 --N concentration, with the most pronounced effect in plantations that are more frequently fertilized. Soil moisture content, IN, NH4 +-N and NO3 --N concentrations within all sites were higher in the rainy season than in the dry season. Significant differences in the soil moisture content, and IN, NH4 +-N and NO3 --N concentration was detected for both land uses and sampling season effects, as well as interactions. Higher concentrations of NH4 +-N were measured at the upper slopes of all sites, but NO3 --N concentrations were highest at the lower slope in the rubber plantations and lowest at the lower slopes at all other. Thus, the conversion of tropical forests to rubber and tea plantations can have a profound effect on soil NH4 +-N and NO3 --N concentrations. Options for improved soil management in plantations are discussed.

  13. Accelerated soil carbon turnover under tree plantations limits soil carbon storage.

    PubMed

    Chen, Guangshui; Yang, Yusheng; Yang, Zhijie; Xie, Jinsheng; Guo, Jianfen; Gao, Ren; Yin, Yunfeng; Robinson, David

    2016-01-01

    The replacement of native forests by tree plantations is increasingly common globally, especially in tropical and subtropical areas. Improving our understanding of the long-term effects of this replacement on soil organic carbon (SOC) remains paramount for effectively managing ecosystems to mitigate anthropogenic carbon emissions. Meta-analyses imply that native forest replacement usually reduces SOC stocks and may switch the forest from a net sink to a net source of atmospheric carbon. Using a long-term chronosequence during which areas of subtropical native forest were replaced by Chinese fir, we show by direct measurement that plantations have significantly accelerated SOC turnover compared with native forest, an effect that has persisted for almost a century. The immediate stimulation of SOC decomposition was caused by warmer soil before the closure of the plantation's canopy. Long-term reductions in SOC mean residence times were coupled to litter inputs. Faster SOC decomposition was associated with lower soil microbial carbon use efficiency, which was due to smaller litter inputs and reduced nutrient availabilities. Our results indicate a previously unelucidated control on long-term SOC dynamics in native forests and demonstrate a potential constraint on climate mitigation when such forests are replaced by plantations. PMID:26805949

  14. Soil carbon storage beneath recently established tree plantations in Tennessee and South Carolina, USA

    SciTech Connect

    Garten Jr, Charles T

    2002-02-01

    Rates of soil carbon (C) accumulation under 7 recently established tree plantations in Tennessee and South Carolina (USA) were estimated by comparing soil C stocks under the plantations to adjacent reference (nonplantation) sites. Estimated rates of C accumulation in surface (0-40 cm) mineral soil were 40-170 gCm{sup -2} yr{sup -1} during the first decade following plantation establishment. Most soil C at each site was found in mineral-associated organic matter (i.e., soil C associated with the silt-clay fraction). Soils with high sand content and low initial C stocks exhibited the greatest gains in particulate organic matter C (POM-C). Labile soil C stocks (consisting of forest floor and mineral soil POM-C) became an increasingly important component of soil C storage as loblolly pine stands aged. Rates of mineral soil C accumulation were highly variable in the first decade of plantation growth, depending on location, but the findings support a hypothesis that farm to tree plantation conversions can result in high initial rates of soil C accumulation in the southeastern United States.

  15. Methanotrophic community abundance and composition in plateau soils with different plant species and plantation ways.

    PubMed

    Dai, Yu; Wu, Zhen; Xie, Shuguang; Liu, Yong

    2015-11-01

    Aerobic methane-oxidizing bacteria (MOB) play an important role in mitigating the methane emission in soil ecosystems to the atmosphere. However, the impact of plant species and plantation ways on the distribution of MOB remains unclear. The present study investigated MOB abundance and structure in plateau soils with different plant species and plantation ways (natural and managed). Soils were collected from unmanaged wild grassland and naturally forested sites, and managed farmland and afforested sites. A large variation in MOB abundance and structure was found in these studied soils. In addition, both type I MOB (Methylocaldum) and type II MOB (Methylocystis) were detected in these soils, while type II MOB usually outnumbered type I MOB. The distribution of soil MOB community was found to be collectively regulated by plantation way, plant species, the altitude of sampling site, and soil properties. PMID:26142389

  16. Soil Carbon Stocks Decrease following Conversion of Secondary Forests to Rubber (Hevea brasiliensis) Plantations

    PubMed Central

    de Blécourt, Marleen; Brumme, Rainer; Xu, Jianchu; Corre, Marife D.; Veldkamp, Edzo

    2013-01-01

    Forest-to-rubber plantation conversion is an important land-use change in the tropical region, for which the impacts on soil carbon stocks have hardly been studied. In montane mainland southeast Asia, monoculture rubber plantations cover 1.5 million ha and the conversion from secondary forests to rubber plantations is predicted to cause a fourfold expansion by 2050. Our study, conducted in southern Yunnan province, China, aimed to quantify the changes in soil carbon stocks following the conversion from secondary forests to rubber plantations. We sampled 11 rubber plantations ranging in age from 5 to 46 years and seven secondary forest plots using a space-for-time substitution approach. We found that forest-to-rubber plantation conversion resulted in losses of soil carbon stocks by an average of 37.4±4.7 (SE) Mg C ha−1 in the entire 1.2-m depth over a time period of 46 years, which was equal to 19.3±2.7% of the initial soil carbon stocks in the secondary forests. This decline in soil carbon stocks was much larger than differences between published aboveground carbon stocks of rubber plantations and secondary forests, which range from a loss of 18 Mg C ha−1 to an increase of 8 Mg C ha−1. In the topsoil, carbon stocks declined exponentially with years since deforestation and reached a steady state at around 20 years. Although the IPCC tier 1 method assumes that soil carbon changes from forest-to-rubber plantation conversions are zero, our findings show that they need to be included to avoid errors in estimating overall ecosystem carbon fluxes. PMID:23894456

  17. Soil carbon stocks decrease following conversion of secondary forests to rubber (Hevea brasiliensis) plantations.

    PubMed

    de Blécourt, Marleen; Brumme, Rainer; Xu, Jianchu; Corre, Marife D; Veldkamp, Edzo

    2013-01-01

    Forest-to-rubber plantation conversion is an important land-use change in the tropical region, for which the impacts on soil carbon stocks have hardly been studied. In montane mainland southeast Asia, monoculture rubber plantations cover 1.5 million ha and the conversion from secondary forests to rubber plantations is predicted to cause a fourfold expansion by 2050. Our study, conducted in southern Yunnan province, China, aimed to quantify the changes in soil carbon stocks following the conversion from secondary forests to rubber plantations. We sampled 11 rubber plantations ranging in age from 5 to 46 years and seven secondary forest plots using a space-for-time substitution approach. We found that forest-to-rubber plantation conversion resulted in losses of soil carbon stocks by an average of 37.4±4.7 (SE) Mg C ha(-1) in the entire 1.2-m depth over a time period of 46 years, which was equal to 19.3±2.7% of the initial soil carbon stocks in the secondary forests. This decline in soil carbon stocks was much larger than differences between published aboveground carbon stocks of rubber plantations and secondary forests, which range from a loss of 18 Mg C ha(-1) to an increase of 8 Mg C ha(-1). In the topsoil, carbon stocks declined exponentially with years since deforestation and reached a steady state at around 20 years. Although the IPCC tier 1 method assumes that soil carbon changes from forest-to-rubber plantation conversions are zero, our findings show that they need to be included to avoid errors in estimating overall ecosystem carbon fluxes. PMID:23894456

  18. Accelerated soil carbon turnover under tree plantations limits soil carbon storage

    NASA Astrophysics Data System (ADS)

    Chen, Guangshui; Yang, Yusheng; Yang, Zhijie; Xie, Jinsheng; Guo, Jianfen; Gao, Ren; Yin, Yunfeng; Robinson, David

    2016-01-01

    The replacement of native forests by tree plantations is increasingly common globally, especially in tropical and subtropical areas. Improving our understanding of the long-term effects of this replacement on soil organic carbon (SOC) remains paramount for effectively managing ecosystems to mitigate anthropogenic carbon emissions. Meta-analyses imply that native forest replacement usually reduces SOC stocks and may switch the forest from a net sink to a net source of atmospheric carbon. Using a long-term chronosequence during which areas of subtropical native forest were replaced by Chinese fir, we show by direct measurement that plantations have significantly accelerated SOC turnover compared with native forest, an effect that has persisted for almost a century. The immediate stimulation of SOC decomposition was caused by warmer soil before the closure of the plantation’s canopy. Long-term reductions in SOC mean residence times were coupled to litter inputs. Faster SOC decomposition was associated with lower soil microbial carbon use efficiency, which was due to smaller litter inputs and reduced nutrient availabilities. Our results indicate a previously unelucidated control on long-term SOC dynamics in native forests and demonstrate a potential constraint on climate mitigation when such forests are replaced by plantations.

  19. Accelerated soil carbon turnover under tree plantations limits soil carbon storage

    PubMed Central

    Chen, Guangshui; Yang, Yusheng; Yang, Zhijie; Xie, Jinsheng; Guo, Jianfen; Gao, Ren; Yin, Yunfeng; Robinson, David

    2016-01-01

    The replacement of native forests by tree plantations is increasingly common globally, especially in tropical and subtropical areas. Improving our understanding of the long-term effects of this replacement on soil organic carbon (SOC) remains paramount for effectively managing ecosystems to mitigate anthropogenic carbon emissions. Meta-analyses imply that native forest replacement usually reduces SOC stocks and may switch the forest from a net sink to a net source of atmospheric carbon. Using a long-term chronosequence during which areas of subtropical native forest were replaced by Chinese fir, we show by direct measurement that plantations have significantly accelerated SOC turnover compared with native forest, an effect that has persisted for almost a century. The immediate stimulation of SOC decomposition was caused by warmer soil before the closure of the plantation’s canopy. Long-term reductions in SOC mean residence times were coupled to litter inputs. Faster SOC decomposition was associated with lower soil microbial carbon use efficiency, which was due to smaller litter inputs and reduced nutrient availabilities. Our results indicate a previously unelucidated control on long-term SOC dynamics in native forests and demonstrate a potential constraint on climate mitigation when such forests are replaced by plantations. PMID:26805949

  20. Impact of Logging and Forest Conversion to Oil Palm Plantations on Soil Bacterial Communities in Borneo

    PubMed Central

    Lee-Cruz, Larisa; Edwards, David P.; Tripathi, Binu M.

    2013-01-01

    Tropical forests are being rapidly altered by logging and cleared for agriculture. Understanding the effects of these land use changes on soil bacteria, which constitute a large proportion of total biodiversity and perform important ecosystem functions, is a major conservation frontier. Here we studied the effects of logging history and forest conversion to oil palm plantations in Sabah, Borneo, on the soil bacterial community. We used paired-end Illumina sequencing of the 16S rRNA gene, V3 region, to compare the bacterial communities in primary, once-logged, and twice-logged forest and land converted to oil palm plantations. Bacteria were grouped into operational taxonomic units (OTUs) at the 97% similarity level, and OTU richness and local-scale α-diversity showed no difference between the various forest types and oil palm plantations. Focusing on the turnover of bacteria across space, true β-diversity was higher in oil palm plantation soil than in forest soil, whereas community dissimilarity-based metrics of β-diversity were only marginally different between habitats, suggesting that at large scales, oil palm plantation soil could have higher overall γ-diversity than forest soil, driven by a slightly more heterogeneous community across space. Clearance of primary and logged forest for oil palm plantations did, however, significantly impact the composition of soil bacterial communities, reflecting in part the loss of some forest bacteria, whereas primary and logged forests did not differ in composition. Overall, our results suggest that the soil bacteria of tropical forest are to some extent resilient or resistant to logging but that the impacts of forest conversion to oil palm plantations are more severe. PMID:24056463

  1. Response of soil respiration and ecosystem carbon budget to vegetation removal in Eucalyptus plantations with contrasting ages

    PubMed Central

    Wu, Jianping; Liu, Zhanfeng; Huang, Guomin; Chen, Dima; Zhang, Weixin; Shao, Yuanhu; Wan, Songze; Fu, Shenglei

    2014-01-01

    Reforested plantations have substantial effects on terrestrial carbon cycling due to their large coverage area. Although understory plants are important components of reforested plantations, their effects on ecosystem carbon dynamics remain unclear. This study was designed to investigate the effects of vegetation removal/understory removal and tree girdling on soil respiration and ecosystem carbon dynamics in Eucalyptus plantations of South China with contrasting ages (2 and 24 years old). We conducted a field manipulation experiment from 2008 to 2009. Understory removal reduced soil respiration in both plantations, whereas tree girdling decreased soil respiration only in the 2-year-old plantations. The net ecosystem production was approximately three times greater in the 2-year-old plantations (13.4 t C ha−1 yr−1) than in the 24-year-old plantations (4.2 t C h−1 yr−1). The biomass increase of understory plants was 12.6 t ha−1 yr−1 in the 2-year-old plantations and 2.9 t ha−1 yr−1 in the 24-year-old plantations, accounting for 33.9% and 14.1% of the net primary production, respectively. Our findings confirm the ecological importance of understory plants in subtropical plantations based on the 2 years of data. These results also indicate that Eucalyptus plantations in China may be an important carbon sink due to the large plantation area. PMID:25179343

  2. Management Effects on Soil Respiration in North Carolina Coastal Plain Loblolly Pine Plantations

    NASA Astrophysics Data System (ADS)

    Gavazzi, M.; McNulty, S.; Noormets, A.; Treasure, E.

    2012-12-01

    Loblolly pine is the most widely planted tree for plantation management in the southern US. In the southern coastal plain, where much of the original longleaf pine and bottomland hardwood forests have been converted to loblolly pine plantations, inland areas are commonly characterized by deep organic soils that can store up to 80 kg C m-2. Intensive management activities on these sites disturb the forest floor and soil and their impact on soil respiration rates and long term soil storage capabilities is unclear. We measured soil respiration rates in three loblolly pine plantations being managed with a combination of ditching, bedding, clearcutting, thinning and fertilization. Sites and management regimes represented a wide range of real world conditions found in managed southern US forestry plantations. Soil efflux rates along with soil temperature and moisture were measured throughout the year at four to six plots on each site and best fit relationships were developed. Annual soil respiration rates where modeled using 30-minute soil temperature and moisture measurements recorded at a centralized meteorological station on each site. Soil efflux rates were highly correlated with soil temperature and moisture, but interaction between the two effects was uncommon. Soil temperature was the primary driver of soil respiration rates, but rates were suppressed under high soil moisture content. Modeled annual soil efflux rates were higher the first two years following clearcut harvest and thinning operations, but lower two years following fertilization. Rates were lower in the gaps, where entire tree rows were removed, compared to thinned areas, especially on the unfertilized site. Results indicate that soil respiration rates can be strongly impacted by forest management practices; however, the period of increased soil CO2 efflux due to site disturbance may last only a few years.

  3. Losses of soil carbon by converting tropical forest to plantations: erosion and decomposition estimated by δ(13) C.

    PubMed

    Guillaume, Thomas; Damris, Muhammad; Kuzyakov, Yakov

    2015-09-01

    Indonesia lost more tropical forest than all of Brazil in 2012, mainly driven by the rubber, oil palm, and timber industries. Nonetheless, the effects of converting forest to oil palm and rubber plantations on soil organic carbon (SOC) stocks remain unclear. We analyzed SOC losses after lowland rainforest conversion to oil palm, intensive rubber, and extensive rubber plantations in Jambi Province on Sumatra Island. The focus was on two processes: (1) erosion and (2) decomposition of soil organic matter. Carbon contents in the Ah horizon under oil palm and rubber plantations were strongly reduced up to 70% and 62%, respectively. The decrease was lower under extensive rubber plantations (41%). On average, converting forest to plantations led to a loss of 10 Mg C ha(-1) after about 15 years of conversion. The C content in the subsoil was similar under the forest and the plantations. We therefore assumed that a shift to higher δ(13) C values in plantation subsoil corresponds to the losses from the upper soil layer by erosion. Erosion was estimated by comparing the δ(13) C profiles in the soils under forest and under plantations. The estimated erosion was the strongest in oil palm (35 ± 8 cm) and rubber (33 ± 10 cm) plantations. The (13) C enrichment of SOC used as a proxy of its turnover indicates a decrease of SOC decomposition rate in the Ah horizon under oil palm plantations after forest conversion. Nonetheless, based on the lack of C input from litter, we expect further losses of SOC in oil palm plantations, which are a less sustainable land use compared to rubber plantations. We conclude that δ(13) C depth profiles may be a powerful tool to disentangle soil erosion and SOC mineralization after the conversion of natural ecosystems conversion to intensive plantations when soils show gradual increase of δ(13) C values with depth. PMID:25707391

  4. [Effects of urbanization on soil nitrogen supply in Pinus elliottii plantations].

    PubMed

    Yu, Ming-quan; Yuan, Ping-cheng; Chen, Fu-sheng; Hu, Xiao-fei; Du, Tian-zhen

    2009-03-01

    With the Pinus elliottii plantations along an urban-rural gradient in Nanchang City as test objectives, and by using ion-exchange resin (IER) bag, this paper studied the seasonal dynamics of soil available nitrogen in the plantations, and analyzed the effects of urbanization on soil nitrogen supply. The results showed that the soil nitrogen supply in the plantations had an obvious seasonal fluctuation. Soil NH4+ -N concentration was significantly higher in autumn and winter than in spring and summer, while soil NO3- -N concentration, mineral N concentration, and relative nitrification rate were in adverse (P < 0.05). The seasonal dynamics of soil available nitrogen was basically consistent with the growth rhythm of P. elliottii. The soil nitrogen availability and relative nitrification ratio along the gradient differed greatly, being significantly higher in urban than in rural area (P < 0.05). Urbanization accelerated soil N mineralization and nitrification, enhanced soil nitrogen supply capacity, and increased soil NO3- -N content. It was suggested that in the construction of urban forest, the plants with high N demand, especially with high NO3- -N absorption capacity, should be introduced to mitigate the soil available N loss and its induced environmental pollution. PMID:19637587

  5. Long lasting effects of the conversion from natural forest to poplar plantation on soil microbial communities.

    PubMed

    Vitali, Francesco; Mastromei, Giorgio; Senatore, Giuliana; Caroppo, Cesarea; Casalone, Enrico

    2016-01-01

    In this study, we evaluate the long-lasting effects on soil microbial communities of a change within a single land-use category, specifically the conversion from natural forest to forest plantation. To minimize the effects of impacts other than land-use (i.e., climatic and anthropogenic), we chose three sites within a Natural Park, with homogeneous orographic and soil texture characteristics. We compared microbial diversity in a total of 156 soil samples from two natural mixed forests and a similar forest converted to poplar plantation about thirty years ago. The diversity and structure of bacterial and fungal communities were investigated by terminal restriction fragments length polymorphism (T-RFLP) analysis of the 16S-rRNA gene and the ITS-rDNA regions, respectively. Bacterial and fungal communities from the forest plantation, compared to those from natural forest soils, showed different community structure and lower α-diversity values, consistently with the significantly higher pH values and lower organic matter content of those soils. β-diversity values, the number of measured and estimated dominant OTUs, and their distribution among the three sites showed that microbial communities from the two natural forests were much more similar to each other than they were to communities from the poplar plantation, suggesting an effect of the forest conversion on the composition and diversity of soil microbial communities. α-diversity in cultivated forest soils had narrower temporal fluctuations than in natural forest soils, suggesting higher temporal stability of microbial communities. Overall, we demonstrated that the conversion from natural forest to forest plantation altered soil microbial communities, changing their structure, lowering their diversity, and causing a spatial and temporal homogenization. PMID:26686617

  6. [Effect of pine plantations on soil arthropods in a high Andean forest].

    PubMed

    León-Gamboa, Alba Lucía; Ramos, Carolina; García, Mary Ruth

    2010-09-01

    One of the most common problems in the Colombian mountains has been the replacement of native vegetation by pine plantations. Soil arthropods are a fundamental component of forest ecosystem, since they participate in the organic matter fragmentation, previous to decomposition. This role is more valuable in high altitude environments, where low temperatures limit the dynamics of biological processes, where the effects of pine plantations on soil arthropods are still not well-known. In a remnant of high-andean forest (Neusa - Colombia) and a pine plantation of about 50 years-old, it was evaluated the composition, richness and abundance of arthropods at surface (S), organic horizon (O) and mineral horizon (A) of soil, to establish the differences associated to the soil use transformation. It was used "Pitfall" sampling to register the movement of the epigeous fauna, and extraction by funnel Berlese for determining the fauna density from O and A horizons. The Shannon and Simpson indexes estimated the diversity at different places and horizons, and the trophic structure of the community was evaluated. Overall, there were collected 38 306 individuals from forest and 17 386 individuals from pine plantation, mainly distributed in Collembola (42.4%), Acari (27%), Diptera (17.6%) and Coleoptera (4.6%). The most important differences were given in the surface, where the mobilization in forest (86 individuals/day) almost triplicates the one in pine plantation (33 individuals/day). The differences in composition were given in Collembola, Araneae, Hemiptera, Homoptera and Hymenoptera. The dynamics of richness and abundance along the year had significant high values in the native forest than in the pine plantation. The general trophic structure was dominated by saprophagous (75%), followed by predators (14%) and phytophagous (9%), but in two layers of the pine plantation soil (S and O) this structural pattern was not given. Based on the results, it was concluded that pine

  7. Forest conversion to poplar plantation in a Lombardy floodplain (Italy): effects on soil organic carbon stock

    NASA Astrophysics Data System (ADS)

    Ferré, C.; Comolli, R.; Leip, A.; Seufert, G.

    2014-06-01

    Effects of forest conversion to poplar plantation on soil organic carbon (SOC) stocks were investigated by sampling paired plots in an alluvial area of the Ticino river in Northern Italy. According to land registers and historical aerial photographs, the two sites were part of a larger area of a 200 years-old natural forest that was partly converted to poplar plantation in 1973. The soil sampling of three layers down to a depth of 100 cm was performed at 90 and 70 points in the natural forest (NF) and in the nearby poplar plantation (PP), respectively. The substitution of the natural forest with the poplar plantation strongly modified soil C stock down to a depth of 55 cm, although the management practices at PP were not intensive. By evaluation of equivalent soil masses, the comparison of C stocks (organic layer included) between the different land uses showed a decrease in SOC of 5.7 kg m-2 after 37 years of poplar cultivation, corresponding to more than 1/3 of the initial organic carbon content. The land use change from NF to PP not only affected the stock but also the vertical distribution of SOC: ploughing led to the transfer of SOC from soil surface into the deeper layers resulting in a more uniform allocation of organic carbon in the ploughed layer and disappearance of the SOC stratification observed in the forest.

  8. [Effects of conversion of natural broad-leaved forest to Chinese fir plantation on soil respiration in subtropical China].

    PubMed

    Zhang, Rui; Bai, Yang; Liu, Juan; Jiang, Pei-kun; Zhou, Guo-mo; Wu, Jia-sen; Tong, Zhi-peng; Li, Yong-fu

    2015-10-01

    Soil CO2 effluxes in natural broad-leaved forest and the conversed Chinese fir plantation in Linglong Mountains Scenic of Zhejiang Province were evaluated by using static closed chamber and gas chromatography method. The results showed that soil CO2 efflux showed consistent seasonal dynamics in natural broad-leaved forest and Chinese fir plantation, with the maximums observed in summer and autumn, the minimums in winter and spring. Soil CO2 effluxes were 20.0-111.3 and 4.1-118.6 mg C . m-2 . h-1 in natural broad-leaved forest and Chinese fir plantation, respectively. The cumulative soil CO2 emission of natural broad-leaved forest (16.46 t CO2 . hm-2 . a-1) was significantly higher than that of Chinese fir plantation (11.99 t CO2 . hm-2 . a-1). Soil moisture did not affect soil CO2 efflux. There was a significant relationship between soil CO2 efflux and soil temperature at 5 cm depth. There was no significant relationship between soil CO2 efflux of natural broad-leaved forest and water soluble organic carbon content, while water soluble organic carbon content affected significantly soil CO2 efflux in Chinese fir plantation. Converting the natural broad-leaved forest to Chinese fir plantation reduced soil CO2 efflux significantly but improved the sensitivity of soil respiration to environmental factors. PMID:26995901

  9. Intercropped silviculture systems, a key to achieving soil fungal community management in eucalyptus plantations.

    PubMed

    Rachid, Caio T C C; Balieiro, Fabiano C; Fonseca, Eduardo S; Peixoto, Raquel Silva; Chaer, Guilherme M; Tiedje, James M; Rosado, Alexandre S

    2015-01-01

    Fungi are ubiquitous and important contributors to soil nutrient cycling, playing a vital role in C, N and P turnover, with many fungi having direct beneficial relationships with plants. However, the factors that modulate the soil fungal community are poorly understood. We studied the degree to which the composition of tree species affected the soil fungal community structure and diversity by pyrosequencing the 28S rRNA gene in soil DNA. We were also interested in whether intercropping (mixed plantation of two plant species) could be used to select fungal species. More than 50,000 high quality sequences were analyzed from three treatments: monoculture of Eucalyptus; monoculture of Acacia mangium; and a mixed plantation with both species sampled 2 and 3 years after planting. We found that the plant type had a major effect on the soil fungal community structure, with 75% of the sequences from the Eucalyptus soil belonging to Basidiomycota and 19% to Ascomycota, and the Acacia soil having a sequence distribution of 28% and 62%, respectively. The intercropping of Acacia mangium in a Eucalyptus plantation significantly increased the number of fungal genera and the diversity indices and introduced or increased the frequency of several genera that were not found in the monoculture cultivation samples. Our results suggest that management of soil fungi is possible by manipulating the composition of the plant community, and intercropped systems can be a means to achieve that. PMID:25706388

  10. Intercropped silviculture systems, a key to achieving soil fungal community management in eucalyptus plantations

    DOE PAGESBeta

    Caio T.C.C. Rachid; Balieiro, Fabiano C.; Fonseca, Eduardo S.; Peixoto, Raquel Silva; Chaer, Guilherme M.; Tiedje, James M.; Rosado, Alexandre S.

    2015-02-23

    Fungi are ubiquitous and important contributors to soil nutrient cycling, playing a vital role in C, N and P turnover, with many fungi having direct beneficial relationships with plants. However, the factors that modulate the soil fungal community are poorly understood. We studied the degree to which the composition of tree species affected the soil fungal community structure and diversity by pyrosequencing the 28S rRNA gene in soil DNA. We were also interested in whether intercropping (mixed plantation of two plant species) could be used to select fungal species. More than 50,000 high quality sequences were analyzed from three treatments:more » monoculture of Eucalyptus; monoculture of Acacia mangium; and a mixed plantation with both species sampled 2 and 3 years after planting. We found that the plant type had a major effect on the soil fungal community structure, with 75% of the sequences from the Eucalyptus soil belonging to Basidiomycota and 19% to Ascomycota, and the Acacia soil having a sequence distribution of 28% and 62%, respectively. The intercropping of Acacia mangium in a Eucalyptus plantation significantly increased the number of fungal genera and the diversity indices and introduced or increased the frequency of several genera that were not found in the monoculture cultivation samples. Our results suggest that management of soil fungi is possible by manipulating the composition of the plant community, and intercropped systems can be a means to achieve that.« less

  11. Intercropped Silviculture Systems, a Key to Achieving Soil Fungal Community Management in Eucalyptus Plantations

    PubMed Central

    Rachid, Caio T. C. C.; Balieiro, Fabiano C.; Fonseca, Eduardo S.; Peixoto, Raquel Silva; Chaer, Guilherme M.; Tiedje, James M.; Rosado, Alexandre S.

    2015-01-01

    Fungi are ubiquitous and important contributors to soil nutrient cycling, playing a vital role in C, N and P turnover, with many fungi having direct beneficial relationships with plants. However, the factors that modulate the soil fungal community are poorly understood. We studied the degree to which the composition of tree species affected the soil fungal community structure and diversity by pyrosequencing the 28S rRNA gene in soil DNA. We were also interested in whether intercropping (mixed plantation of two plant species) could be used to select fungal species. More than 50,000 high quality sequences were analyzed from three treatments: monoculture of Eucalyptus; monoculture of Acacia mangium; and a mixed plantation with both species sampled 2 and 3 years after planting. We found that the plant type had a major effect on the soil fungal community structure, with 75% of the sequences from the Eucalyptus soil belonging to Basidiomycota and 19% to Ascomycota, and the Acacia soil having a sequence distribution of 28% and 62%, respectively. The intercropping of Acacia mangium in a Eucalyptus plantation significantly increased the number of fungal genera and the diversity indices and introduced or increased the frequency of several genera that were not found in the monoculture cultivation samples. Our results suggest that management of soil fungi is possible by manipulating the composition of the plant community, and intercropped systems can be a means to achieve that. PMID:25706388

  12. Intercropped silviculture systems, a key to achieving soil fungal community management in eucalyptus plantations

    SciTech Connect

    Caio T.C.C. Rachid; Balieiro, Fabiano C.; Fonseca, Eduardo S.; Peixoto, Raquel Silva; Chaer, Guilherme M.; Tiedje, James M.; Rosado, Alexandre S.

    2015-02-23

    Fungi are ubiquitous and important contributors to soil nutrient cycling, playing a vital role in C, N and P turnover, with many fungi having direct beneficial relationships with plants. However, the factors that modulate the soil fungal community are poorly understood. We studied the degree to which the composition of tree species affected the soil fungal community structure and diversity by pyrosequencing the 28S rRNA gene in soil DNA. We were also interested in whether intercropping (mixed plantation of two plant species) could be used to select fungal species. More than 50,000 high quality sequences were analyzed from three treatments: monoculture of Eucalyptus; monoculture of Acacia mangium; and a mixed plantation with both species sampled 2 and 3 years after planting. We found that the plant type had a major effect on the soil fungal community structure, with 75% of the sequences from the Eucalyptus soil belonging to Basidiomycota and 19% to Ascomycota, and the Acacia soil having a sequence distribution of 28% and 62%, respectively. The intercropping of Acacia mangium in a Eucalyptus plantation significantly increased the number of fungal genera and the diversity indices and introduced or increased the frequency of several genera that were not found in the monoculture cultivation samples. Our results suggest that management of soil fungi is possible by manipulating the composition of the plant community, and intercropped systems can be a means to achieve that.

  13. [Soil microbial community structure of monoculture and mixed plantation stands of native tree species in south subtropical China].

    PubMed

    Luo, Da; Shi, Zuo-Min; Tang, Jing-Chao; Liu, Shi-Rong; Lu, Li-Hua

    2014-09-01

    The effects of three plantation stands, Erythrophleumf ordii (EF), Pinus massoniana (PM), and their mixed plantation (MP), on soil microbial biomass and microbial community structure in south subtropical China were studied by the method of phospholipid fatty acids (PLFAs) analysis. The results showed that the amounts of microbial total PLFAs and PLFAs of each microbial group in these three plantation stand soils were significantly higher in dry season than in rainy season. In dry season, the amounts of microbial total PLFAs, bacteria PLFAs, fungi PLFAs, and actinomycetes PLFAs were the highest in the PM soil, moderate in the MP soil, and the lowest in the EF soil. But in rainy season, the amounts of microbial total PLFAs, bacteria PLFAs, fungi PLFAs, and arbuscular mycorrhizal fungi (AMF) PLFAs in the EF soil were higher than in the MP soil, and were significantly higher than in the PM soil. Principal component analysis (PCA) indicated that the variations in soil microbial community structure composition were affected by both plantation types and seasons. Redundancy analysis (RDA) of soil microbial community structure and environmental factors showed that soil temperature and moisture, pH, total nitrogen content, and ammonium nitrogen content had significant correlations with PLFA signatures. In addition, the ratio of fungi PLFAs to bacteria PLFAs in the MP soil was the highest among the three stand soils within the whole year, indicating that mixed plantation stands could facilitate the stability of the soil ecosystem. PMID:25757303

  14. Observation of Soil Water Repellency and pH soil change under Tropical Pine Plantations Compared with Native Tropical Forest

    NASA Astrophysics Data System (ADS)

    Robinson, D. A.; Lebron, I.; Oatham, M. P.; Wuddivira, M. N.

    2011-12-01

    In temperate climates, soil water repellency (SWR) has been documented to develop with land-use change from native forest to pine plantations. In the tropics a sparse evidence base has been documented for the observation of SWR, but no investigation has been conducted to determine the consequences of changing land-use from native forest to pine plantations with regard to SWR. In our research we broaden the evidence base for tropical SWR by comparing the SWR behavior of seven tropical pine plantations in Trinidad with co-located native forest. We found that SWR occurred under both pine and native forest, but was more persistent and less heterogeneous under pine. The SWR was water content dependent with a threshold ~0.2 m3m-3, it showed a linear dependence with litter depth, and it was also found to be pH dependent, being higher in more acidic soils. The forest floor pH, contrary to convention for temperate climates, was observed to increase under some pine plantations, as compared with native tropical forest. This only occurred in the very acidic tropical soils (pH<4), but may have important biogeochemical consequences with regard to soil and water quality.

  15. Soil water repellency and pH soil change under tropical pine plantations compared with native tropical forest

    NASA Astrophysics Data System (ADS)

    Lebron, Inma; Robinson, David A.; Oatham, Mike; Wuddivira, Mark N.

    2012-01-01

    SummaryIn temperate climates, soil water repellency (SWR) has been documented to develop with land-use change from native forest to pine plantations. In the tropics a sparse evidence base has been documented for the observation of SWR, but no investigation has been conducted to determine the consequences of changing land-use from native forest to pine plantations with regard to SWR. In our research we broaden the evidence base for tropical SWR by comparing the SWR behavior of seven tropical pine plantations in Trinidad with co-located native forest. We found that SWR occurred under both pine and native forest, but was more persistent and less heterogeneous under pine. The SWR was water content dependent with a threshold ˜0.2 m 3 m -3, it showed a linear dependence with litter depth, and it was also found to be higher in more acidic soils. The forest floor pH, contrary to convention for temperate climates, was observed to increase under some pine plantations, as compared with native tropical forest. This only occurred in the very acidic tropical soils (pH < 4), but may have important biogeochemical consequences with regard to soil and water quality.

  16. [Distribution pattern of meso-micro soil fauna in Eucalyptus grandis plantation].

    PubMed

    Huang, Yumei; Zhang, Jian; Yang, Wanqin

    2006-12-01

    In this paper, meso-micro soil fauna were extracted and collected by Baermann's and Tullgren' s method, and their distribution pattern in the Eucalyptus grandis plantation of Hongya County, Sichuan Province was studied. A total of 13 550 specimens were collected, belonging to 6 phyla, 13 classes, and 26 orders. Acarina, Nematoda, Collembola were the dominant groups, and Enchytraeidae was the frequent one. The group and individual numbers of meso-micro soil fauna varied with seasons, being the maximum in autumn or winter, fewer in summer, and the minimum in spring. The density of meso-micro soil fauna in soil profile decreased rapidly with increasing soil depth, but a converse distribution was observed from time to time in 5 - 10 cm and 10 - 15 cm soil layers. The meso-micro soil fauna collected by Baermann's and Tullgren's method had a density of 3. 333 x 10(3) - 2. 533 x 10(5) ind x m(-2) and 1.670 x 10(2) - 2.393 x 10(5) ind x m(-2), respectively, and the decreasing rate of the density with the increase of soil depth was higher for those collected by Tullgren's method. The density-group index of meso-micro soil fauna in the E. grandis plantation was the lowest in spring, but the highest in autumn or summer. There were no significant differences in the density of meso-micro soil fauna and in the density-group index between E. grandis plantation and Quercus acutissima secondary forest. PMID:17330474

  17. Forest conversion to poplar plantation in a Lombardy floodplain (Italy): effects on soil organic carbon stock

    NASA Astrophysics Data System (ADS)

    Ferré, C.; Comolli, R.; Leip, A.; Seufert, G.

    2014-11-01

    Effects of forest conversion to poplar plantation on soil organic carbon (SOC) stocks were investigated by sampling paired plots in an alluvial area of the Ticino River in Northern Italy. According to land registers and historical aerial photographs, the two sites were part of a larger area of a 200 yr old natural forest that was partly converted to poplar plantation in 1973. The soil sampling of three layers down to a depth of 100 cm was performed at 90 and 70 points in the natural forest (NF) and in the nearby poplar plantation (PP) respectively. The substitution of the natural forest with the poplar plantation strongly modified soil C stock down to a depth of 55 cm, although the management practices at PP were not intensive. After calculation of equivalent soil masses and of SOC stocks in individual texture classes, the comparison of C stocks showed an overall decrease in SOC of 5.7 kg m-2 or 40% in consequence of 37 years of poplar cultivation. Our case study provides further evidence that (i) spatial heterogeneity of SOC is an important feature in paired plot studies requiring a careful sampling strategy and high enough number of samples; (ii) land use changes through tillage are creating a more homogeneous spatial structure of soil properties and may require the application of dedicated spatial statistics to tackle eventual problems of pseudo-replicates and auto-correlation; (iii) short rotation forests are not properly represented in current reporting schemes for changes of SOC after land use change and may better be considered as cropland.

  18. Forest thinning and soil respiration in a ponderosa pine plantation in the Sierra Nevada.

    PubMed

    Tang, Jianwu; Qi, Ye; Xu, Ming; Misson, Laurent; Goldstein, Allen H

    2005-01-01

    Soil respiration is controlled by soil temperature, soil water, fine roots, microbial activity, and soil physical and chemical properties. Forest thinning changes soil temperature, soil water content, and root density and activity, and thus changes soil respiration. We measured soil respiration monthly and soil temperature and volumetric soil water continuously in a young ponderosa pine (Pinus ponderosa Dougl. ex P. Laws. & C. Laws.) plantation in the Sierra Nevada Mountains in California from June 1998 to May 2000 (before a thinning that removed 30% of the biomass), and from May to December 2001 (after thinning). Thinning increased the spatial homogeneity of soil temperature and respiration. We conducted a multivariate analysis with two independent variables of soil temperature and water and a categorical variable representing the thinning event to simulate soil respiration and assess the effect of thinning. Thinning did not change the sensitivity of soil respiration to temperature or to water, but decreased total soil respiration by 13% at a given temperature and water content. This decrease in soil respiration was likely associated with the decrease in root density after thinning. With a model driven by continuous soil temperature and water time series, we estimated that total soil respiration was 948, 949 and 831 g C m(-2) year(-1) in the years 1999, 2000 and 2001, respectively. Although thinning reduced soil respiration at a given temperature and water content, because of natural climate variability and the thinning effect on soil temperature and water, actual cumulative soil respiration showed no clear trend following thinning. We conclude that the effect of forest thinning on soil respiration is the combined result of a decrease in root respiration, an increase in soil organic matter, and changes in soil temperature and water due to both thinning and interannual climate variability. PMID:15519986

  19. Soil C and N changes with afforestation of grasslands across gradients of precipitation and plantation age.

    PubMed

    Berthrong, Sean T; Piñeiro, Gervasio; Jobbágy, Esteban G; Jackson, Robert B

    2012-01-01

    Afforestation, the conversion of unforested lands to forests, is a tool for sequestering anthropogenic carbon dioxide into plant biomass. However, in addition to altering biomass, afforestation can have substantial effects on soil organic carbon (SOC) pools, some of which have much longer turnover times than plant biomass. An increasing body of evidence suggests that the effect of afforestation on SOC may depend on mean annual precipitation (MAP). The goal of this study was to test how labile and bulk pools of SOC and total soil nitrogen (TN) change with afforestation across a rainfall gradient of 600-1500 mm in the Rio de la Plata grasslands of Argentina and Uruguay. The sites were all former grasslands planted with Eucalyptus spp. Overall, we found that afforestation increased (up to 1012 kg C x ha(-1) x yr(-1)) or decreased (as much as 1294 kg C x ha(-1) x yr(-1)) SOC pools in this region and that these changes were significantly related to MAP. Drier sites gained, and wetter sites lost, SOC and TN (r2 = 0.59, P = 0.003; and r2 = 0.57, P = 0.004, respectively). Labile C and N in microbial biomass and extractable soil pools followed similar patterns to bulk SOC and TN. Interestingly, drier sites gained more SOC and TN as plantations aged, while losses reversed as plantations aged in wet sites, suggesting that plantation age in addition to precipitation is a critical driver of changes in soil organic matter with afforestation. This new evidence implies that longer intervals between harvests for plantations could improve SOC storage, ameliorating the negative trends found in humid sites. Our results suggest that the value of afforestation as a carbon sequestration tool should be considered in the context of precipitation and age of the forest stand. PMID:22471076

  20. Changes in soil quality due to converting Pinus to Eucalyptus plantations and subsequent successive Eucalyptus planting in southern China

    NASA Astrophysics Data System (ADS)

    Zhang, K.; Zheng, H.; Chen, F. L.; Ouyang, Z. Y.; Wang, Y.; Wu, Y. F.; Lan, J.; Fu, M.; Xiang, X. W.

    2014-09-01

    Plants play a key role in maintaining soil quality, but long-term changes in soil quality due to plant species change and successive planting are rarely reported. Using the space-for-time substitution method, adjacent plantations of Pinus and 1st, 2nd, 3rd and 4th generations of Eucalyptus in Guangxi, China were used to study changes in soil quality caused by converting Pinus to Eucalyptus and successive Eucalyptus planting. Soil chemical and biological properties were measured and a soil quality index (SQI) was calculated. Soil organic carbon, total nitrogen, alkaline hydrolytic nitrogen, microbial biomass carbon, microbial biomass nitrogen, cellobiosidase, phenol oxidase, peroxidase and acid phosphatase activities significantly decreased in the 1st and 2nd generations of Eucalyptus plantations after conversion from Pinus to Eucalyptus but gradually recovered in the 3rd and 4th generations. Soil total and available potassium were significantly lower, but total phosphorus was significantly higher in Eucalyptus plantations compared to the Pinus plantation. As an integrated indicator, SQI was highest in the Pinus plantation (0.92), but decreased to 0.24 and 0.13 in the 1st and 2nd generations of Eucalyptus plantations, respectively. However, it recovered to 0.36 and 0.38 in the 3rd and 4th generations, respectively. Changing tree species, reclamation and fertilization may have contributed to the "U" shaped change observed in soil quality during conversion of Pinus to Eucalyptus and successive Eucalyptus planting. Litter retention, keeping understory coverage, and reducing soil disturbance during logging and subsequent establishment of the next rotation should be considered to help improving soil quality during plantation management.

  1. Physico-chemical properties of soil at oil palm plantation area, Labu, Negeri Sembilan

    NASA Astrophysics Data System (ADS)

    Rozieta, R.; Sahibin A., R.; Wan Mohd Razi, I.

    2015-09-01

    A study on the physico-chemical characteristics of soil from oil palm plantation area at New Labu Estate, Negeri Sembilan was carried out. A number of 20 topsoil (0-20cm) samples were collected based on plantation block by using `Dutch Auger'. The soil physico-chemical properties determined were particle size distribution, organic matter content, pH and total organic carbon. Particle size distribution was determined by pipette method and dry sieving. Bulk density was determined by waxing method. Organic matter and total organic carbon were measured through loss of ignition and Walkley-Black method, respectively. Soil pH was determined based on soil:water ratio of 1:2.5. Results showed that the texture of the soil was classified as sandy clay with the highest percentage of sand particles component. Organic matter content is considered as low at less than 4% and soil organic carbon content was low with 1.75%. The average soil pH in the study area was very acidic with values of 3.81.

  2. Modeling relationships between water table depth and peat soil carbon loss in Southeast Asian plantations

    NASA Astrophysics Data System (ADS)

    Carlson, Kimberly M.; Goodman, Lael K.; May-Tobin, Calen C.

    2015-07-01

    Plantation-associated drainage of Southeast Asian peatlands has accelerated in recent years. Draining exposes the upper peat layer to oxygen, leading to elevated decomposition rates and net soil carbon losses. Empirical studies indicate positive relationships between long-term water table (WT) depth and soil carbon loss rate in peatlands. These correlations potentially enable using WT depth as a proxy for soil carbon losses from peatland plantations. Here, we compile data from published research assessing WT depth and carbon balance in tropical plantations on peat. We model net carbon loss from subsidence studies, as well as soil respiration (heterotrophic and total) from closed chamber studies, as a function of WT depth. WT depth across all 12 studies and 59 sites is 67 ± 20 cm (mean ± standard deviation). Mean WT depth is positively related to net carbon loss, as well as soil respiration rate. Our models explain 45% of net carbon loss variation and 45-63% of soil respiration variation. At a 70 cm WT depth, the subsidence model suggests net carbon loss of 20 tC ha-1 yr-1 (95% confidence interval (CI) 18-22 tC ha-1 yr-1) for plantations drained for >2 yr. Closed chamber-measured total soil respiration at this depth is 20 tC-CO2 ha-1 yr-1 (CI 17-24 tC-CO2 ha-1 yr-1) while heterotrophic respiration is 17 tC-CO2 ha-1 yr-1 (CI 14-20 tC-CO2 ha-1 yr-1), ˜82% of total respiration. While land use is not a significant predictor of soil respiration, WT depths are greater at acacia (75 ± 16 cm) than oil palm (59 ± 15 cm) sample sites. Improved spatio-temporal sampling of the full suite of peat soil carbon fluxes—including fluvial carbon export and organic fertilizer inputs—will clarify multiple mechanisms leading to carbon loss and gain, supporting refined assessments of the global warming potential of peatland drainage.

  3. Soil nitrate leaching in silvopastures compared with open pasture and pine plantation.

    PubMed

    Bambo, Susan K; Nowak, Jarek; Blount, Ann R; Long, Alan J; Osiecka, Anna

    2009-01-01

    Wide acceptance of silvopasture as an alternative sustainable agricultural system in the southeastern United States will depend on an improved understanding of the tree-forage interactions and recognition of its environmental benefits. The objective of this study was to evaluate differences in soil nitrate leaching in different land-use systems, in north Florida. An 18-yr-old loblolly pine (Pinus taeda L.) plantation was thinned in the summer of 2002 to create a fifth-row thinned, nontraditional intensive pine plantation (FO), silvopastures (HE = fourth-row conventionally thinned with random tree distribution and DO = double-row sets of trees with 15-m wide alleys), and an open pasture (PA). 'Argentine' bahiagrass (Paspalum notatum Flügge.) was established as understory vegetation in HE, DO, and PA. From 2004 to 2005 soil nitrate leaching was sampled and compared in the DO, HE, PA, and FO systems at 0.3 and 1.2 m depths after fertilizer application. Significant nitrate peaks were observed at 0.3 m depth after N fertilizer application in all systems. At the 1.2 m depth, the maximum nitrate concentrations were 67, 18, and 8 mg L(-1), in the forest plantation, open pasture, and both silvopastures, respectively. In general, reduced nitrate leaching at 1.2 m depth was observed in silvopastures compared with other land-used systems. These results are not intended to have a direct bearing on traditional pine plantation management, but rather support the potential role of silvopasture systems in reducing nitrate losses from the soil. PMID:19643752

  4. Conversion of grazing land into Grevillea robusta plantation and exclosure: impacts on soil nutrients and soil organic carbon.

    PubMed

    Alem, Shiferaw; Pavlis, Jindrich

    2014-07-01

    Different studies have shown that the effect of land use conversion on soil nutrients and soil organic carbon (SOC) is variable, which indicates that more investigations that focus on different specific geographical locations and land use types are required. The objectives of this study were (1) to evaluate the effect of grazing land (GL) conversion into Grevillea robusta plantation and exclosure (EX) on soil nutrients and soil organic carbon (SOC) and (2) to examine the impact of soil organic matter (SOM) on soil nutrients. To achieve these objectives, soil samples were taken from a soil depth of 20 cm (n = 4) in each of the studied land areas. Each soil sample was analysed in a soil laboratory following a standard procedure. Analysis of variance (ANOVA) and Pearson's correlation coefficient were used for the data analysis. The result indicated that conversion of GL into EX improved the soil electrical conductivity (EC), exchangeable K, cation exchange capacity (CEC), total N and available P (p < 0.05), while the exchangeable Mg, SOC, available K and SOM were decreased (p < 0.05). Conversion of GL into G. robusta improved the soil EC, exchangeable (K, Ca, Mg), CEC, SOC, total N, available K and SOM (p < 0.05). There was a significant relationship between SOM and available P, total N, SOC and EC. There were no significant relationships between SOM and pH, available K and CEC. Finally, the results indicate that both land uses, established in acidic Nitosols, have variable impacts on soil chemical properties and that G. robusta plantation improved most of the soil nutrients and SOC much better than the EX land use. PMID:24696281

  5. Nitrate Distribution in Soil Moisture and Groundwater with Intensive Plantation Management on Abandoned Agricultural Land

    SciTech Connect

    Williams, T.M.

    1998-01-01

    Paper outlines nitrate leaching results of loblolly pine and sweet gum that were grown with irrigation, continuous fertilization and insect pest control on a year old abandoned peanut field. Wells and tension lysimeters were used to measure nitrate in soil moisture and groundwater on three replicate transects for two years. Groundwater nitrate concentration beneath the minimum treatment was much higher than the maximum treatment and old field. All three treatments often exceeded the drinking water standard. Forest and lake edge had low levels while the soil moisture nitrate concentrations in the two plantations treatments were much higher than the old field.

  6. Estimation of Soil Erosion Rates in Oil Palm Plantation with Different Land Cover

    NASA Astrophysics Data System (ADS)

    Sahat, S.; Yusop, Z.; Askari, M.; Ziegler, A. D.

    2016-07-01

    Soil losses from hill slopes in oil palm plantation in Sedenak Estate, Johor were measured using runoff plot and rainfall simulator. The plot was designed to be removable but the size was fixed at 8 x 3.75m. Four types of surface covers were investigated for the plots, i.e. half bare soil and half grass cover (HGC), half bare soil and half dry frond (HDF), fully grass cover (FG), and fully bare soil (BS). The influence of initial soil moisture, saturated hydraulics conductivity, Ks, bulk density and slope on rates of soil loss were also evaluated. The rainfall simulator produced rainfall intensities between 90 and 160 mm/hr with durations from 45 to 60 min per run. BS plot exhibited the highest Ks value among all plots but the percentage of initial soil moisture on this surface was low. BS plot recorded the highest runoff coefficient (C) and soil loss values of 73.6 ± 4 percent and 5.26 ± 3.2 t/ha respectively, while the lowest was from plot FG with 41.7 ± 5.7 percent and soil loss of 2.85 ± 2.1 t/ha. Meanwhile, the results suggested that the ground cover had the ability to reduce soil loss by 67% and 17%, respectively for plots BS-HGC and BS-HDF. Overall, soil erosion control such as surface is effective measures in reducing level of runoff and soil erosion.

  7. [Dynamic changes in soil respiration components and their regulating factors in the Moso bamboo plantation in subtropical China].

    PubMed

    Yang, Wen-jia; Li, Yong-fu; Jiang, Pei-kun; Zhou, Guo-mo; Liu, Juan

    2015-10-01

    Dynamic changes (from April 2013 to March 2014) in soil respiration components were investigated by Li-8100 in the Moso bamboo plantation in Lin' an City, Zhejiang Province. Results showed that the average annual values for the soil total respiration rate, heterotrophic respiration rate, and autotrophic respiration rate in the Moso bamboo plantation were 2.93, 1.92 and 1.01 imol CO2 . m-2 . s-1, respectively. The soil respiration rate and its components exhibited strongly a seasonal dynamic pattern. The maximum appeared in July 2013, and the minimum appeared in January 2014. The annual cumulative CO2 emissions through soil respiration, heterotrophic respiration, and autotrophic respiration were 37.25, 24.61 and 12.64 t CO2 . hm-2 . a-1, respectively. The soil respiration and its components showed a close relation with soil temperature of 5 cm depth, and the corresponding Q10, values at 5 cm depth were 2.05, 1.95 and 2.34, respectively. Both the soil respiration and heterotrophic respiration were correlated to soil water soluble organic C (WSOC) content, but no significant relationship between autotrophic respiration and WSOC was observed. There were no significant relationships between soil respiration components and soil moisture content or microbial biomass C. The seasonal changes in soil respiration components in the Moso bamboo plantation were predominantly controlled by the soil temperature, and the soil WSOC content was an important environmental factor controlling total soil respiration and soil heterotrophic respiration. PMID:26995900

  8. Rainforest Conversion to Rubber Plantation May Not Result in Lower Soil Diversity of Bacteria, Fungi, and Nematodes.

    PubMed

    Kerfahi, Dorsaf; Tripathi, Binu M; Dong, Ke; Go, Rusea; Adams, Jonathan M

    2016-08-01

    Large areas of rainforest in Asia have been converted to plantations, with uncertain effects on soil biodiversity. Using standard metagenetic methods, we compared the soil biota of bacteria, fungi, and nematodes at three rainforest sites in Malaysia with two rubber plantation sites with similar soils and geology. We predicted the following: (1) that the rubber sites would have a lower α- and β-diversity than the rainforest sites, due to the monospecific canopy cover and intensive management with herbicides, pesticides, and fertilizers, and (2) that due to differences in the physical and biotic environment associated with cultivation, there would be distinct communities of bacteria, fungi, and nematodes. However, regarding (1), the results showed no consistent difference in α- and β-diversity of bacteria, fungi, or nematodes between rainforest and rubber plantation sites. It appears that conversion of rainforest to rubber plantations does not necessarily result in a decrease in diversity of soil biota. It may be that heterogeneity associated with the cultivation regimen compensates for loss of biotically imposed heterogeneity of the original rainforest. Regarding (2), as predicted there were statistically significant differences in community composition between rainforest and rubber plantation for bacteria, fungi, and nematodes. These differences could be related to a range of factors including light level, litter fall composition, pH, C and N, selecting a distinct set of soil taxa, and it is possible that this in itself would affect long-term soil function. PMID:27221090

  9. Spatial variability of some soil properties varies in oil palm (Elaeis guineensis Jacq.) plantations of west coastal area of India

    NASA Astrophysics Data System (ADS)

    Behera, Sanjib Kumar; Suresh, Kancherla; Narsimha Rao, Bezawada; Mathur, Ravi Kumar; Shukla, Arvind Kumar; Manorama, Kamireddy; Ramachandrudu, Kummari; Harinarayana, Parasa; Prakash, Chandra

    2016-06-01

    Mapping spatial variability of soil properties is the key to efficient soil resource management for sustainable crop yield. Therefore, the present study was conducted to assess the spatial variability of soil properties such as acidity (pH), salinity (electrical conductivity (EC)), organic carbon, available K, available P, exchangeable Ca2+, exchangeable Mg2+, available S and hot water soluble B in surface (0-20 cm) and subsurface (20-40 cm) soil layers of oil palm plantations in south Goa district of Goa located in west coastal area of India. A total of 128 soil samples were collected from 64 oil palm plantations of Goa located at an approximate interval of 1-2 km and analyzed. Soil was acidic to neutral in reaction. Other soil properties varied widely in both the soil layers. Correlations between soil pH and exchangeable Ca2+, between soil EC and available K, between available P and available S and between exchangeable Ca2+ and exchangeable Mg2+ in both the soil layers were found to be positive and significant (P < 0.01). Geostatistical analysis revealed a varied spatial distribution pattern for the measured soil properties. Best-fit models for measured soil properties were exponential, Gaussian, stable, K-Bessel and spherical with moderate to strong spatial dependency. The results revealed that site-specific fertilizer management options needed to be adopted in the oil palm plantations of the study area owing to variability in soil properties.

  10. Extreme soil erosion rates in citrus slope plantations and control strategies. A literature review

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; Ángel González Peñaloza, Félix; Pereira, Paulo; Reyes Ruiz Gallardo, José; García Orenes, Fuensanta; Burguet, María

    2013-04-01

    Soil Erosion is a natural process that shapes the Earth. Due to the impact of agriculture, soil erosion rates increase, landforms show gullies and rills, and soils are depleted. In the Mediterranean, wheat, olive and vineyards were the main agriculture products, but new plantations are being found in sloping terrain due to the drip-irrigation. This new strategy results in the removal of the traditional terraces in order to make suitable for mechanization the agriculture plantation. Citrus is a clear example of the impact of the new chemical agriculture with a high investment in herbicides, pesticides, mechanisation, land levelling and drip computer controlled irrigation systems. The new plantation of citrus orchards is found in the Mediterranean, but also in California, Florida, China and Brazil. Chile, Argentina, and South Africa are other producers that are moving to an industrial production of citrus. This paper shows how the citrus plantations are found as one of the most aggressive plantation due to the increase in soil erosion, and how we can apply successful control strategies. The research into the high erosion rates of citrus orchard built on the slopes are mainly found in China (Wu et al., 1997; Xu et al., 2010; Wang et al., 2011; Wu et al., 2011; Liu et al., 2011; Lü et al., 2011; Xu et al., 2012) and in the Mediterranean (Cerdà and Jurgensen, 2008; 2009; Cerdà et al., 2009a; 2009b; Cerdà et al., 2011; 2012) Most of the research done devoted to the measurements of the soil losses but also some research is done related to the soil properties (Lu et al., 1997; Lü et al., 2012; Xu et al., 2012) and the impact of cover crops to reduce the soil losses (Lavigne et al., 2012; Le Bellec et al., 2012) and the use of residues such as dried citrus peel in order to reduce the soil losses. There are 116 million tonnes of citrus produced yearly, and this affects a large surface of the best land. The citrus orchards are moving from flood irrigated to drip

  11. [Effects of simulated nitrogen deposition on soil enzyme activities in a Betula luminifera plantation in Rainy Area of West China].

    PubMed

    Tu, Li-Hua; Hu, Hong-Ling; Hu, Ting-Xing; Zhang, Jian; Xiao, Yin-Long; Luo, Shou-Hua; Li, Ren-Hong; Dai, Hong-Zhong

    2012-08-01

    From January 2008 to January 2009, a field experiment was conducted to investigate the effects of simulated nitrogen (N) deposition (0, 5, 15, and 30 g N x m(-2) x a(-1)) on the soil enzyme activities in a Betula luminifera plantation in Rainy Area of West China. As compared with the control (0 g N x m(-2) x a(-1)), simulated N deposition stimulated the activities of soil hydrolases (beta-fructofuranosidase, cellulase, acid phosphatase, and urease) significantly, but depressed the activities of soil oxidases (polyphenol oxidase and peroxidase). These results suggested that the increased exogenous inorganic N could stimulate soil microbial activity and increase the demands of both B. luminifera and soil microbes for C and P, whereas the depress of soil polyphenol oxidase and peroxidase activities under N addition could inhibit the degradation of litter and promote its accumulation in soil, leading to the increase of soil C storage in the B. luminifera plantation ecosystem. PMID:23189689

  12. The influence of mature oak stands and spruce plantations on soil-dwelling click beetles in lowland plantation forests.

    PubMed

    Loskotová, Tereza; Horák, Jakub

    2016-01-01

    Most European forests have been converted into forest plantations that are managed for timber production. The main goal of this paper was to determine the difference between mature native sessile oak (Quercus petraea) stands and non-indigenous Norway spruce (Picea abies) plantations, with respect to communities of Athous click beetles in approximately 6,500 ha of lowland plantation forest area in the Czech Republic. Athous subfuscus was the most abundant and widespread species, followed by A. zebei and A. haemorrhoidalis, while A. vittatus was considered rare. Spatial analysis of environmental variables inside studied patches showed that the species composition of Athous beetles best responded to a 20 m radius surrounding traps. The species' responses to the environment showed that A. vittatus and A. haemorrhoidalis preferred oak stands, while A. zebei and A. subfuscus were associated with spruce plantations. In addition, oak stands showed higher diversity of beetle communities. The studied species are important for their ecosystem services (e.g. predation on pests or bioturbation) and seem to tolerate certain degrees of human disturbances, which is especially beneficial for forest plantations managed for timber production. PMID:26793425

  13. The influence of mature oak stands and spruce plantations on soil-dwelling click beetles in lowland plantation forests

    PubMed Central

    Loskotová, Tereza

    2016-01-01

    Most European forests have been converted into forest plantations that are managed for timber production. The main goal of this paper was to determine the difference between mature native sessile oak (Quercus petraea) stands and non-indigenous Norway spruce (Picea abies) plantations, with respect to communities of Athous click beetles in approximately 6,500 ha of lowland plantation forest area in the Czech Republic. Athous subfuscus was the most abundant and widespread species, followed by A. zebei and A. haemorrhoidalis, while A. vittatus was considered rare. Spatial analysis of environmental variables inside studied patches showed that the species composition of Athous beetles best responded to a 20 m radius surrounding traps. The species’ responses to the environment showed that A. vittatus and A. haemorrhoidalis preferred oak stands, while A. zebei and A. subfuscus were associated with spruce plantations. In addition, oak stands showed higher diversity of beetle communities. The studied species are important for their ecosystem services (e.g. predation on pests or bioturbation) and seem to tolerate certain degrees of human disturbances, which is especially beneficial for forest plantations managed for timber production. PMID:26793425

  14. Effect of soil acidification induced by a tea plantation on chemical and mineralogical properties of Alfisols in eastern China.

    PubMed

    Alekseeva, T; Alekseev, A; Xu, Ren-Kou; Zhao, An-Zhen; Kalinin, P

    2011-04-01

    The effect of a tea plantation on soil basic properties, chemical and mineralogical compositions, and magnetic properties of Alfisols from eastern China was studied. Under the tea plantation, acidification took place within a soil depth of 70 cm, with the maximum difference in pH in the upper 17 cm (ΔpH = 2.80). Both the tea plantation and unused soil profiles were predominated by free Fe and Al oxides, i.e. citrate/bicarbonate/dithionite extractable Fe (Fe(d)) and Al (Al(d)). Tea plantation soil was characterized by higher Al(d) and Fe(d) and lower Fe oxalate, Fe(2)O(3) and Al(2)O(3); CaO was depleted, whereas SiO(2) accumulated. Acidification induced by the tea plantation led to destruction of vermiculite followed by dissolution of the hydroxy-Al interlayers within its structure. The data clearly demonstrated that significant soil weathering occurred with acidification caused by tea cultivation. This acidification also resulted in decreased content of ferrimagnetic minerals due to the dissolution of minerals and movement of Fe in the profile. PMID:20563880

  15. Diminishing soil carbon stocks caused by the land-use change from secondary forests to terraced rubber plantations

    NASA Astrophysics Data System (ADS)

    de Blecourt, Marleen; Brumme, Rainer; Haensel, Maria V.; Corre, Marife D.; Xu, Jianchu; Veldkamp, Edzo

    2013-04-01

    Conversion from forest to rubber plantations (Hevea Brasiliensis) is an important recent land-use change in the Upper Mekong Region in Southeast Asia, for which the impacts on soil carbon stocks have hardly been studied. Due to the mountainous topography most of the established rubber plantations include narrow terraces. Terrace bench construction involves redistribution of the soil within the plantations. The objectives of our study in Xishuangbanna prefecture, Yunnan province, China were: to quantify the changes in soil carbon stocks (1) upon the conversion from secondary forest to rubber plantations, and (2) induced by terrace bench construction. We selected seven randomly selected clusters. Each cluster contained between one and three rubber plantations and one secondary forest which was the immediate reference land-use type. In total, there were 11 rubber plantations ranging in age from 5 to 46 years. In each land-use type, we measured soil carbon stock from a 20-m x 20-m plot down to 1.2-m depth. To gain insight into the effects of terracing, we additionally sampled the terrace benches in three rubber plantations aged 5, 29 and 44 years. In each plantation, six transect were positioned perpendicularly to terrace benches. Each transect consisted of 4 sampling points on the terrace bench and one sampling point on the undisturbed terrace riser, the latter is our reference position. All rubber plantations had lower soil carbon stocks than the forests with a mean difference of 37.4 Mg C ha-1 in the entire 1.2-m depth, which equals a 19% loss of the initial soil carbon stock. Strongest decrease was found in the top 0.15-m of the soil, exhibiting a mean loss of 27%. In the topsoil the soil carbon stock declined exponentially with years since land-use conversion and reached a steady state after ~20 years. The soil carbon losses observed in this study are much larger than published estimates on changes in aboveground carbon stocks. Results from the terracing case

  16. [Soil greenhouse gases emission from an Acacia crassicarpa plantation under effects of understory removal and Cassia alata addition].

    PubMed

    Li, Hai-Fang; Zhang, Xing-Feng

    2010-03-01

    Forest soil is one of the main sources of greenhouse gases CO2, CH4, and N2O. By using static chamber and GS technique, this paper measured in situ the CO2, CH4, and N2O fluxes of Acacia crassicarpa plantation in Heshan Hilly Land Interdisciplinary Experimental Station under Chinese Academy of Sciences (CAS), and studied the soil CO2, CH4 and N2O emissions from the plantation under effects of understory removal and Cassia alata addition. The CO2 flux of the plantation maintained at a higher level during rainy season but decreased obviously in dry season, while the CH4 and N2O fluxes varied widely from September to November, with the peaks in October. Under the effects of understory removal and C. alata addition, the soil in the plantation could be a sink or a source of CH4, but consistently a source of CO2 and N2O. Understory removal enhanced the soil CO2 emission (P < 0.05 ), C. alata addition increased the soil CH4 emission (P < 0.05), while both understory removal and C. alata addition increased the soil N2O emission (P < 0.05). Surface soil temperature, moisture content, NO3(-) -N concentration, and microbial biomass carbon were the main factors affecting the soil CO2, CH4 and N2O emissions. PMID:20560308

  17. Effect of inter-row cultivation on soil CO2 emission in a peach plantation

    NASA Astrophysics Data System (ADS)

    Tóth, E.; Farkas, Cs.; Gelybó, Gy.; Lagzi, I.

    2012-04-01

    We examined the effect of inter-row cultivation on soil CO2 emission in a peach plantation planted in 1991. The soil is Ramann type brown forest soil /Mollic Cambisol/ developed on sandy loam. Every second row in the orchard is covered with undisturbed grass, and every other row is disked (depth: 12-15cm) with a two-three-week frequency. The humus content varies from 1,69% to 2,28% in the upper 20 cm layer, where the sand, loam and clay contents are 58%, 21% and 19 %, respectively. The average annual precipitation total is 570 mm (330 mm for the growing season) at the site. During the vegetation period of 2009 soil CO2 emission measurements were carried out with static chamber method in the differently managed rows. Parallel with CO2 measurements soil volumetric water content and soil temperature were also determined. Soil microbiological properties water-extractable organic carbon (WEOC) and water-extractable nitrogen (WEN) as well as substrate-induced respiration (SIR) were determined from disturbed soil samples collected on the first measurement day. The measured soil physical properties showed that different soil management practices influence soil water content, bulk density and soil temperature as well. Soil water content was higher in the grass covered row on 10 of the 13 measurement days, the difference - which reached 10 v% - was the highest on the warmest days. Soil temperature is also different in case of disked and grass covered rows, found to be lower in the grass covered rows on every measurement days. SIR, WEOC and WEN were all higher in the grass covered row (19.45 μg CO2-C g-1 soil 36.91 μg g-1 soil, 139.36 μg g-1 soil, respectively) than in the disked row (4.88 μg CO2-C g-1 soil 25.43 μg C g-1 soil, 61.25 μg N g-1 soil, respectively) in 2009. Soil CO2 emission also differed between the two rows, grass covered rows produced higher emission in all measurements days without exemption. The difference between CO2 fluxes from the two cultivation

  18. Extreme soil erosion rates in citrus slope plantations and control strategies. A literature review

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; Ángel González Peñaloza, Félix; Pereira, Paulo; Reyes Ruiz Gallardo, José; García Orenes, Fuensanta; Burguet, María

    2013-04-01

    Soil Erosion is a natural process that shapes the Earth. Due to the impact of agriculture, soil erosion rates increase, landforms show gullies and rills, and soils are depleted. In the Mediterranean, wheat, olive and vineyards were the main agriculture products, but new plantations are being found in sloping terrain due to the drip-irrigation. This new strategy results in the removal of the traditional terraces in order to make suitable for mechanization the agriculture plantation. Citrus is a clear example of the impact of the new chemical agriculture with a high investment in herbicides, pesticides, mechanisation, land levelling and drip computer controlled irrigation systems. The new plantation of citrus orchards is found in the Mediterranean, but also in California, Florida, China and Brazil. Chile, Argentina, and South Africa are other producers that are moving to an industrial production of citrus. This paper shows how the citrus plantations are found as one of the most aggressive plantation due to the increase in soil erosion, and how we can apply successful control strategies. The research into the high erosion rates of citrus orchard built on the slopes are mainly found in China (Wu et al., 1997; Xu et al., 2010; Wang et al., 2011; Wu et al., 2011; Liu et al., 2011; Lü et al., 2011; Xu et al., 2012) and in the Mediterranean (Cerdà and Jurgensen, 2008; 2009; Cerdà et al., 2009a; 2009b; Cerdà et al., 2011; 2012) Most of the research done devoted to the measurements of the soil losses but also some research is done related to the soil properties (Lu et al., 1997; Lü et al., 2012; Xu et al., 2012) and the impact of cover crops to reduce the soil losses (Lavigne et al., 2012; Le Bellec et al., 2012) and the use of residues such as dried citrus peel in order to reduce the soil losses. There are 116 million tonnes of citrus produced yearly, and this affects a large surface of the best land. The citrus orchards are moving from flood irrigated to drip

  19. [Litter decomposition and nutrient release in Acacia mangium plantations established on degraded soils of Colombia].

    PubMed

    Castellanos-Barliza, Jeiner; León Peláez, Juan Diego

    2011-03-01

    Several factors control the decomposition in terrestrial ecosystems such as humidity, temperature, quality of litter and microbial activity. We investigated the effects of rainfall and soil plowing prior to the establishment of Acacia mangium plantations, using the litterbag technique, during a six month period, in forests plantations in Bajo Cauca region, Colombia. The annual decomposition constants (k) of simple exponential model, oscillated between 1.24 and 1.80, meanwhile k1 y k2 decomposition constants of double exponential model were 0.88-1.81 and 0.58-7.01. At the end of the study, the mean residual dry matter (RDM) was 47% of the initial value for the three sites. We found a slow N, Ca and Mg release pattern from the A. mangium leaf litter, meanwhile, phosphorus (P) showed a dominant immobilization phase, suggesting its low availability in soils. Chemical leaf litter quality parameters (e.g. N and P concentrations, C/N, N/P ratios and phenols content) showed an important influence on decomposition rates. The results of this study indicated that rainfall plays an important role on the decomposition process, but not soil plowing. PMID:21516640

  20. Bioaccessible arsenic in soils of former sugar cane plantations, Island of Hawaii.

    PubMed

    Cutler, William G; Brewer, Roger C; El-Kadi, Aly; Hue, Nguyen V; Niemeyer, Patrick G; Peard, John; Ray, Chittaranjan

    2013-01-01

    Arsenical herbicides were used extensively for emergent weed control in Hawaiian sugar cane cultivation from 1913 to about 1950. As a result, surface soil arsenic concentrations average 280 mg kg(-1) across more than 60 km(2) of former sugar plantation land in the eastern portion of the Island of Hawaii. This study was conducted to elucidate the relationship between soil properties and arsenic bioaccessibility in the iron-rich volcanic soils. Soils are predominantly Andisols, formed by weathering of basaltic lava and tephra, with pedogenic solid phases consisting of short-range order iron oxyhydroxides, allophane-like aluminosilicates, and metal-humus compounds. These reactive solid phases strongly adsorb oxyanions, such as phosphate and arsenite/arsenate. High arsenic sorption capacity limits desorption and vertical migration within the soil column and prevents contamination of the underlying groundwater aquifer, despite high arsenic loading and precipitation rates. In vitro arsenic bioaccessibility, as measured by the SBRC gastric-phase test, ranges from 2% to 35% and averages 9% of total arsenic. Bioaccessible arsenic is higher in less weathered soils (Udifolists, Typic and Lithic Hydrudands) and lower in more weathered ash-dominant soils (Acrudoxic Hydrudands). Soil weathering indicators, such as reactive iron content, are strong predictors of arsenic bioaccessibility. Based on evidence from soil mineralogy, geochemistry and arsenic speciation, as well as limited soil arsenic bioavailability/bioaccessibility comparisons, risks to human health from direct contact (soil ingestion) are significantly reduced by low arsenic bioaccessibility. Nonetheless, some soils within former sugar cane cultivation areas contain bioaccessible arsenic concentrations exceeding Hawaii Department of Health risk-based action levels, and will require mitigating actions. Even higher levels of soil arsenic contamination have been identified at former pesticide storage and mixing areas

  1. Invasion of moso bamboo into a Japanese cedar plantation affects the chemical composition and humification of soil organic matter.

    PubMed

    Wang, Hsueh-Ching; Tian, Guanglong; Chiu, Chih-Yu

    2016-01-01

    Bamboo, which has dense culms and root rhizome systems, can alter soil properties when it invades adjacent forests. Therefore, this study investigated whether bamboo invasions can cause changes in soil organic matter (SOM) composition and soil humification. We combined solid-state (13)C NMR spectroscopy and chemical analysis to examine the SOM in a Japanese cedar (Cryptomeria japonica) and adjacent bamboo (Phyllostachys edulis) plantation. Bamboo reduced soil organic C (SOC) content, compared to the cedar plantation. The value of ∆logK (ratio of absorbance of humic acids at 400 and 600 nm) was cedar > transition zone > bamboo soils. Our results indicated that bamboo increased SOM humification, which could be due to the fast decomposition of bamboo litter with the high labile C. Furthermore, intensive management in the bamboo plantation could enhance the humification as well. Overall, litter type can control an ecosystem's SOC nature, as reflected by the finding that higher labile C in bamboo litter contributed the higher ratios of labile C to SOC and lower ratios of recalcitrant C to SOC in bamboo soils compared with cedar soils. The invasion of bamboo into the Japanese cedar plantation accelerated the degradation of SOM. PMID:27558833

  2. Invasion of moso bamboo into a Japanese cedar plantation affects the chemical composition and humification of soil organic matter

    PubMed Central

    Wang, Hsueh-Ching; Tian, Guanglong; Chiu, Chih-Yu

    2016-01-01

    Bamboo, which has dense culms and root rhizome systems, can alter soil properties when it invades adjacent forests. Therefore, this study investigated whether bamboo invasions can cause changes in soil organic matter (SOM) composition and soil humification. We combined solid-state 13C NMR spectroscopy and chemical analysis to examine the SOM in a Japanese cedar (Cryptomeria japonica) and adjacent bamboo (Phyllostachys edulis) plantation. Bamboo reduced soil organic C (SOC) content, compared to the cedar plantation. The value of ∆logK (ratio of absorbance of humic acids at 400 and 600 nm) was cedar > transition zone > bamboo soils. Our results indicated that bamboo increased SOM humification, which could be due to the fast decomposition of bamboo litter with the high labile C. Furthermore, intensive management in the bamboo plantation could enhance the humification as well. Overall, litter type can control an ecosystem’s SOC nature, as reflected by the finding that higher labile C in bamboo litter contributed the higher ratios of labile C to SOC and lower ratios of recalcitrant C to SOC in bamboo soils compared with cedar soils. The invasion of bamboo into the Japanese cedar plantation accelerated the degradation of SOM. PMID:27558833

  3. Spatial variability of soil nutrient in paddy plantation: Sites FELCRA Seberang Perak

    NASA Astrophysics Data System (ADS)

    Kamarudin, H.; Adnan, N. A.; Mispan, M. R.; Athirah. A, A.

    2016-06-01

    The conventional methods currently used for rice cultivation in Malaysia are unable to give maximum yield although the yield production of paddy is increasing. This is due to the conversional method being unable to include soil properties as one of their parameters in agriculture management. Soil properties vary spatially in farm scale due to differences in topography, parent material, vegetation or land management and soil characteristics; also plantation productivity varies significantly over small spatial scales. Knowledge of spatial variability in soil fertility is important for site specific nutrient management. Analysis of spatial variability of soil nutrient of nitrogen (N), phosphorus (P) and potassium (K) were conducted in this study with the aid of GIS (i.e ArcGIS) and statistical softwares. In this study different temporal and depths of soil nutrient were extracted on the field and further analysis of N,P,K content were analysed in the chemical laboratory and using spatially technique in GIS sofware. The result indicated that for the Seberang Perak site of 58 hactares area, N and K are met minimum requirements nutrient content as outlines by the MARDI for paddy cultivation. However, P indicated poor condition in the study area; therefore the soil needs further attention and treatment.

  4. Production, soil erosion and economic failure in new citrus plantations in Eastern Spain

    NASA Astrophysics Data System (ADS)

    Giménez Morera, Antonio; Carles membrado, Joan; Cerdà, Artemi; Ángel González Peñaloza, Félix

    2013-04-01

    their neighboring mountain slopes. The interest of orange groves is not only economic, but also environmental. Although the traditional farming developed a beautiful man made landscape of terraces and irrigation ditches, the development of new irrigation systems by means of drips contributed to new plantations that removed the ditches and the terraces. Those changes are triggering intense soil erosion rates such were shown by previous researchers in Valencia (Cerdà et al., 2009). This impact is also shown in other regions with a similar citrus production evolution, and China is a clear example (Wang et al., 2010; Liu et al., 2012). This research evaluates the production and the cost of production, the economic investment in the establishment of the new citrus plantations and the revenues of 5 farms in the Canyoles river watershed in Eastern Spain. The soil erosion rates measured by means of rainfall simulation experiments in each farm by means of thunderstorms of 10 years return period (55 mm h-1) and by five-year survey by means of topographical measurements. The results show that the soil losses in the new plantation are extremely high, that the investments in the new plantation reached 18352 € ha-1 and that the revenues do not cover the expenses of production. Soil erosion measured since 2007 to 2011 show values that range from 7.54 to 56.76 Mg ha-1 year-1 and show a mean value of 28.45 Mg ha-1 year-1. Rainfall simulation experiments shown that the soil losses were very high as other researched found in new citrus plantations. The comparison with other land uses and agriculture crop and managements shown that soil erosion is higher in then new chemically treated plantations (Cerdà, 2002), and even higher that on road embankments (Cerdà, 2007) and rainfed agriculture soil (García Orenes et al., 2009), although the water repellency found was very low in comparison to organic farming orange plantations (González et al., 2012). The current situation of a high

  5. Complementary soil water use is indicated in mixed native tree plantations, Panama

    NASA Astrophysics Data System (ADS)

    Schwendenmann, L.; Sánchez Bragado, R.; Kunert, N.; Hölscher, D.

    2010-12-01

    Recent approaches to reforestation in the tropics emphasize the establishment of mixed species plantations to provide production but also ecological benefits. However, little is known about the effects of mixed-species stands on soil water utilization und tree water use rates. The objectives of this study were i) to asses seasonal plant water uptake patterns for different species and ii) to examine the effects of species diversity on water uptake and water use rates. The study was conducted in a 7-yr-old plantation in Panama. Five native tree species were planted in mono-, three- and five-species plots. Natural abundance stable isotopic ratios of hydrogen (δ2H) and oxygen (δ18O) in xylem and soil water samples were used to determine water uptake patterns. The contribution of water from each soil layer to xylem water was calculated using the isotope mixing model SISUS (Stable Isotope Sourcing Using Sampling). Sap flux was measured using thermal dissipation probes. Isotope ratios in soil and xylem water fell below the local meteoric water line (LMWL) suggesting some evaporation. Soil water isotope ratio increased with depth from an average of -18 ‰ and -1 ‰ in the surface soil layer (0-10 cm) to -40 ‰ and -8 ‰ at 50-70 cm depth for δ2H and δ18O, respectively. During the dry season δ2H and δ18O of xylem water were negatively correlated with tree water use rates suggesting that trees taking up water from deeper soil horizons were able to maintain higher water use rates. Species tended to differ in their water uptake pattern, especially during the dry season. Cedrela odorata and Hura crepitans were primarily obtaining water (60 to 80%) from the upper 30 cm. In contrast, Tabebuia rosea took up most of its water (75-90%) from soil depths > 30 cm. Xylem water δ2H and δ18O in Anacardium excelsum and Luehea seemannii suggest that water was taken up to equal proportions from all soil horizons. In mixed stands, overall transpirational water use was higher than

  6. Production, soil erosion and economic failure in new citrus plantations in Eastern Spain

    NASA Astrophysics Data System (ADS)

    Giménez Morera, Antonio; Carles membrado, Joan; Cerdà, Artemi; Ángel González Peñaloza, Félix

    2013-04-01

    their neighboring mountain slopes. The interest of orange groves is not only economic, but also environmental. Although the traditional farming developed a beautiful man made landscape of terraces and irrigation ditches, the development of new irrigation systems by means of drips contributed to new plantations that removed the ditches and the terraces. Those changes are triggering intense soil erosion rates such were shown by previous researchers in Valencia (Cerdà et al., 2009). This impact is also shown in other regions with a similar citrus production evolution, and China is a clear example (Wang et al., 2010; Liu et al., 2012). This research evaluates the production and the cost of production, the economic investment in the establishment of the new citrus plantations and the revenues of 5 farms in the Canyoles river watershed in Eastern Spain. The soil erosion rates measured by means of rainfall simulation experiments in each farm by means of thunderstorms of 10 years return period (55 mm h-1) and by five-year survey by means of topographical measurements. The results show that the soil losses in the new plantation are extremely high, that the investments in the new plantation reached 18352 € ha-1 and that the revenues do not cover the expenses of production. Soil erosion measured since 2007 to 2011 show values that range from 7.54 to 56.76 Mg ha-1 year-1 and show a mean value of 28.45 Mg ha-1 year-1. Rainfall simulation experiments shown that the soil losses were very high as other researched found in new citrus plantations. The comparison with other land uses and agriculture crop and managements shown that soil erosion is higher in then new chemically treated plantations (Cerdà, 2002), and even higher that on road embankments (Cerdà, 2007) and rainfed agriculture soil (García Orenes et al., 2009), although the water repellency found was very low in comparison to organic farming orange plantations (González et al., 2012). The current situation of a high

  7. Soil-atmosphere trace gas exchange from tropical oil palm plantations on peat

    NASA Astrophysics Data System (ADS)

    Arn Teh, Yit; Manning, Frances; Zin Zawawi, Norliyana; Hill, Timothy; Chocholek, Melanie; Khoon Kho, Lip

    2015-04-01

    Oil palm is the largest agricultural crop in the tropics, accounting for 13 % of all tropical land cover. Due to its large areal extent, oil palm cultivation may have important implications not only for terrestrial stores of C and N, but may also impact regional and global exchanges of material and energy, including fluxes of trace gases and water vapor. In particular, recent expansion of oil palm into tropical peatlands has raised concerns over enhanced soil C emissions from degradation of peat, and elevated N-gas fluxes linked to N fertilizer application. Here we report our preliminary findings on soil carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes from a long-term, multi-scale project investigating the C, N and greenhouse gas (GHG) dynamics of oil palm ecosystems established on peat soils in Sarawak, Malaysian Borneo. Flux chamber measurements indicate that soil CO2, CH4 and N2O fluxes averaged 20.0 ± 16.0 Mg CO2-C ha-1 yr-1, 37.4 ± 29.9 kg CH4-C ha-1 yr-1 and 4.7 ± 4.2 g N2O-N ha-1 yr-1, respectively. Soil CO2 fluxes were on par with other drained tropical peatlands; whereas CH4 fluxes exceeded observations from similar study sites elsewhere. Nitrous oxide fluxes were in a similar range to fluxes from other drained tropical peatlands, but lower than emissions from mineral-soil plantations by up to three orders of magnitude. Fluxes of soil CO2 and N2O were spatially stratified, and contingent upon the distribution of plants, deposited harvest residues, and soil moisture. Soil CO2 fluxes were most heavily influenced by the distribution of palms and their roots. On average, autotrophic (root) respiration accounted for approximately 78 % of total soil CO2 flux, and total soil respiration declined steeply away from palms; e.g. soil CO2 fluxes in the immediate 1 m radius around palms were up to 6 times greater than fluxes in inter-palm spaces due to higher densities of roots. Placement of harvest residues played an important - but secondary

  8. Nitrogen deposition and management practices increase soil microbial biomass carbon but decrease diversity in Moso bamboo plantations

    NASA Astrophysics Data System (ADS)

    Li, Quan; Song, Xinzhang; Gu, Honghao; Gao, Fei

    2016-06-01

    Because microbial communities play a key role in carbon (C) and nitrogen (N) cycling, changes in the soil microbial community may directly affect ecosystem functioning. However, the effects of N deposition and management practices on soil microbes are still poorly understood. We studied the effects of these two factors on soil microbial biomass carbon (MBC) and community composition in Moso bamboo plantations using high-throughput sequencing of the 16S rRNA gene. Plantations under conventional (CM) or intensive management (IM) were subjected to one of four N treatments for 30 months. IM and N addition, both separately and in combination, significantly increased soil MBC while decreasing bacterial diversity. However, increases in soil MBC were inhibited when N addition exceeded 60 kg N•ha‑1•yr‑1. IM increased the relative abundances of Actinobacteria and Crenarchaeota but decreased that of Acidobacteria. N addition increased the relative abundances of Acidobacteria, Crenarchaeota, and Actinobacteria but decreased that of Proteobacteria. Soil bacterial diversity was significantly related to soil pH, C/N ratio, and nitrogen and available phosphorus content. Management practices exerted a greater influence over regulation of the soil MBC and microbial diversity compared to that of N deposition in Moso bamboo plantations.

  9. Nitrogen deposition and management practices increase soil microbial biomass carbon but decrease diversity in Moso bamboo plantations

    PubMed Central

    Li, Quan; Song, Xinzhang; Gu, Honghao; Gao, Fei

    2016-01-01

    Because microbial communities play a key role in carbon (C) and nitrogen (N) cycling, changes in the soil microbial community may directly affect ecosystem functioning. However, the effects of N deposition and management practices on soil microbes are still poorly understood. We studied the effects of these two factors on soil microbial biomass carbon (MBC) and community composition in Moso bamboo plantations using high-throughput sequencing of the 16S rRNA gene. Plantations under conventional (CM) or intensive management (IM) were subjected to one of four N treatments for 30 months. IM and N addition, both separately and in combination, significantly increased soil MBC while decreasing bacterial diversity. However, increases in soil MBC were inhibited when N addition exceeded 60 kg N∙ha−1∙yr−1. IM increased the relative abundances of Actinobacteria and Crenarchaeota but decreased that of Acidobacteria. N addition increased the relative abundances of Acidobacteria, Crenarchaeota, and Actinobacteria but decreased that of Proteobacteria. Soil bacterial diversity was significantly related to soil pH, C/N ratio, and nitrogen and available phosphorus content. Management practices exerted a greater influence over regulation of the soil MBC and microbial diversity compared to that of N deposition in Moso bamboo plantations. PMID:27302857

  10. Nitrogen deposition and management practices increase soil microbial biomass carbon but decrease diversity in Moso bamboo plantations.

    PubMed

    Li, Quan; Song, Xinzhang; Gu, Honghao; Gao, Fei

    2016-01-01

    Because microbial communities play a key role in carbon (C) and nitrogen (N) cycling, changes in the soil microbial community may directly affect ecosystem functioning. However, the effects of N deposition and management practices on soil microbes are still poorly understood. We studied the effects of these two factors on soil microbial biomass carbon (MBC) and community composition in Moso bamboo plantations using high-throughput sequencing of the 16S rRNA gene. Plantations under conventional (CM) or intensive management (IM) were subjected to one of four N treatments for 30 months. IM and N addition, both separately and in combination, significantly increased soil MBC while decreasing bacterial diversity. However, increases in soil MBC were inhibited when N addition exceeded 60 kg N∙ha(-1)∙yr(-1). IM increased the relative abundances of Actinobacteria and Crenarchaeota but decreased that of Acidobacteria. N addition increased the relative abundances of Acidobacteria, Crenarchaeota, and Actinobacteria but decreased that of Proteobacteria. Soil bacterial diversity was significantly related to soil pH, C/N ratio, and nitrogen and available phosphorus content. Management practices exerted a greater influence over regulation of the soil MBC and microbial diversity compared to that of N deposition in Moso bamboo plantations. PMID:27302857

  11. Soil Microbial Community Structure and Metabolic Activity of Pinus elliottii Plantations across Different Stand Ages in a Subtropical Area

    PubMed Central

    Wu, Zeyan; Haack, Stacey Elizabeth; Lin, Wenxiong; Li, Bailian; Wu, Linkun; Fang, Changxun; Zhang, Zhixing

    2015-01-01

    Soil microbes play an essential role in the forest ecosystem as an active component. This study examined the hypothesis that soil microbial community structure and metabolic activity would vary with the increasing stand ages in long-term pure plantations of Pinus elliottii. The phospholipid fatty acids (PLFA) combined with community level physiological profiles (CLPP) method was used to assess these characteristics in the rhizospheric soils of P. elliottii. We found that the soil microbial communities were significantly different among different stand ages of P. elliottii plantations. The PLFA analysis indicated that the bacterial biomass was higher than the actinomycic and fungal biomass in all stand ages. However, the bacterial biomass decreased with the increasing stand ages, while the fungal biomass increased. The four maximum biomarker concentrations in rhizospheric soils of P. elliottii for all stand ages were 18:1ω9c, 16:1ω7c, 18:3ω6c (6,9,12) and cy19:0, representing measures of fungal and gram negative bacterial biomass. In addition, CLPP analysis revealed that the utilization rate of amino acids, polymers, phenolic acids, and carbohydrates of soil microbial community gradually decreased with increasing stand ages, though this pattern was not observed for carboxylic acids and amines. Microbial community diversity, as determined by the Simpson index, Shannon-Wiener index, Richness index and McIntosh index, significantly decreased as stand age increased. Overall, both the PLFA and CLPP illustrated that the long-term pure plantation pattern exacerbated the microecological imbalance previously described in the rhizospheric soils of P. elliottii, and markedly decreased the soil microbial community diversity and metabolic activity. Based on the correlation analysis, we concluded that the soil nutrient and C/N ratio most significantly contributed to the variation of soil microbial community structure and metabolic activity in different stand ages of P

  12. Simulated biomass and soil carbon of loblolly pine and cottonwood plantations across a thermal gradient in southeastern United States

    SciTech Connect

    Luxmoore, Robert J; Tharp, M Lynn; Post, Wilfred M

    2008-01-01

    Changes in biomass and soil carbon with nitrogen fertilization were simulated for a 25-year loblolly pine (Pinus taeda) plantation and for three consecutive 7-year short-rotation cottonwood (Populus deltoides) stands. Simulations were conducted for 17 locations in the southeastern United States with mean annual temperatures ranging from 13.1 to 19.4 C. The LINKAGES stand growth model, modified to include the "RothC" soil C and soil N model, simulated tree growth and soil C status. Nitrogen fertilization significantly increased cumulative cottonwood aboveground biomass in the three rotations from a site average of 106 to 272 Mg/ha in 21 years, whereas the equivalent site averages for loblolly pine were unchanged at 176 and 184 Mg/ha in 25 years. Location results, compared on the annual sum of daily mean air temperatures above 5.5 C (growing-degree-days), showed contrasts. Loblolly pine biomass increased whereas cottonwood decreased with increasing growing-degree-days, particularly in cottonwood stands receiving N fertilization. The increment of biomass due to N addition per unit of control biomass (relative response) declined in both plantations with increase in growing-degree-days. Average soil C in loblolly pine stands increased from 24.3 to 40.4 Mg/ha in 25 years and in cottonwood soil C decreased from 14.7 to 13.7 Mg/ha after three 7-year rotations. Soil C did not decrease with increasing growing-degree-days in either plantation type suggesting that global warming may not initially affect soil C. Nitrogen fertilizer increased soil C slightly in cottonwood plantations and had no significant effect on the soil C of loblolly stands.

  13. Draft Genome Sequence of the Polyhydroxyalkanoate-Producing Bacterium Burkholderia sacchari LMG 19450 Isolated from Brazilian Sugarcane Plantation Soil

    PubMed Central

    Alexandrino, Paulo Moises Raduan; Mendonça, Thatiane Teixeira; Guamán Bautista, Linda Priscila; Cherix, Juliano; Lozano-Sakalauskas, Gabriela Cazonato; Fujita, André; Ramos Filho, Edmar; Long, Paul; Padilla, Gabriel; Taciro, Marilda Keico; Gomez, José Gregório Cabrera

    2015-01-01

    Burkholderia sacchari LMG 19450, isolated from the soil of a sugarcane plantation in Brazil, accumulates large amounts of polyhydroxyalkanoates from sucrose, xylose, other carbohydrates, and organic acids. We present the draft genome sequence of this industrially relevant bacterium, which is 7.2 Mb in size and has a G+C content of 64%. PMID:25953171

  14. Losses of soil organic carbon by converting tropical forest to plantations: Assessment of erosion and decomposition by new δ13C approach

    NASA Astrophysics Data System (ADS)

    Guillaume, Thomas; Muhammad, Damris; Kuzyakov, Yakov

    2015-04-01

    Indonesia lost more tropical forest than all of Brazil in 2012, mainly driven by the rubber, oil palm and timber industries. Nonetheless, the effects of converting forest to oil palm and rubber plantations on soil organic carbon (SOC) stocks remain unclear. We analyzed SOC losses after lowland rainforest conversion to oil palm, intensive rubber and extensive rubber plantations in Jambi province on Sumatra Island. We developed and applied a new δ13C based approach to assess and separate two processes: 1) erosion and 2) decomposition. Carbon contents in the Ah horizon under oil palm and rubber plantations were strongly reduced: up to 70% and 62%, respectively. The decrease was lower under extensive rubber plantations (41%). The C content in the subsoil was similar in the forest and the plantations. We therefore assumed that a shift to higher δ13C values in the subsoil of the plantations corresponds to the losses of the upper soil layer by erosion. Erosion was estimated by comparing the δ13C profiles in the undisturbed soils under forest with the disturbed soils under plantations. The estimated erosion was the strongest in oil palm (35±8 cm) and rubber (33±10 cm) plantations. The 13C enrichment of SOC used as a proxy of its turnover indicates a decrease of SOC decomposition rate in the Ah horizon under oil palm plantations after forest conversion. SOC availability, measured by microbial respiration rate and Fourier Transformed Infrared Spectroscopy, was lower under oil palm plantations. Despite similar trends in C losses and erosion in intensive plantations, our results indicate that microorganisms in oil palm plantations mineralized mainly the old C stabilized prior to conversion, whereas microorganisms under rubber plantations mineralized the fresh C from the litter, leaving the old C pool mainly untouched. Based on the lack of C input from litter, we expect further losses of SOC under oil palm plantations, which therefore are a less sustainable land

  15. Responses of soil microbial communities and enzyme activities to nitrogen and phosphorus additions in Chinese fir plantations of subtropical China

    NASA Astrophysics Data System (ADS)

    Dong, W. Y.; Zhang, X. Y.; Liu, X. Y.; Fu, X. L.; Chen, F. S.; Wang, H. M.; Sun, X. M.; Wen, X. F.

    2015-07-01

    Nitrogen (N) and phosphorus (P) additions to forest ecosystems are known to influence various above-ground properties, such as plant productivity and composition, and below-ground properties, such as soil nutrient cycling. However, our understanding of how soil microbial communities and their functions respond to nutrient additions in subtropical plantations is still not complete. In this study, we added N and P to Chinese fir plantations in subtropical China to examine how nutrient additions influenced soil microbial community composition and enzyme activities. The results showed that most soil microbial properties were responsive to N and/or P additions, but responses often varied depending on the nutrient added and the quantity added. For instance, there were more than 30 % greater increases in the activities of β-Glucosidase (βG) and N-acetyl-β-D-glucosaminidase (NAG) in the treatments that received nutrient additions compared to the control plot, whereas acid phosphatase (aP) activity was always higher (57 and 71 %, respectively) in the P treatment. N and P additions greatly enhanced the PLFA abundanceespecially in the N2P treatment, the bacterial PLFAs (bacPLFAs), fungal PLFAs (funPLFAs) and actinomycic PLFAs (actPLFAs) were about 2.5, 3 and 4 times higher, respectively, than in the CK. Soil enzyme activities were noticeably higher in November than in July, mainly due to seasonal differences in soil moisture content (SMC). βG or NAG activities were significantly and positively correlated with microbial PLFAs. There were also significant relationships between gram-positive (G+) bacteria and all three soil enzymes. These findings indicate that G+ bacteria is the most important microbial community in C, N, and P transformations in Chinese fir plantations, and that βG and NAG would be useful tools for assessing the biogeochemical transformation and metabolic activity of soil microbes. We recommend combined additions of N and P fertilizer to promote soil

  16. Fungal soil communities in a young transgenic poplar plantation form a rich reservoir for fungal root communities

    PubMed Central

    Danielsen, L; Thürmer, A; Meinicke, P; Buée, M; Morin, E; Martin, F; Pilate, G; Daniel, R; Polle, A; Reich, M

    2012-01-01

    Fungal communities play a key role in ecosystem functioning. However, only little is known about their composition in plant roots and the soil of biomass plantations. The goal of this study was to analyze fungal biodiversity in their belowground habitats and to gain information on the strategies by which ectomycorrhizal (ECM) fungi form colonies. In a 2-year-old plantation, fungal communities in the soil and roots of three different poplar genotypes (Populus × canescens, wildtype and two transgenic lines with suppressed cinnamyl alcohol dehydrogenase activity) were analyzed by 454 pyrosequencing targeting the rDNA internal transcribed spacer 1 (ITS) region. The results were compared with the dynamics of the root-associated ECM community studied by morphotyping/Sanger sequencing in two subsequent years. Fungal species and family richness in the soil were surprisingly high in this simple plantation ecosystem, with 5944 operational taxonomic units (OTUs) and 186 described fungal families. These findings indicate the importance that fungal species are already available for colonization of plant roots (2399 OTUs and 115 families). The transgenic modification of poplar plants had no influence on fungal root or soil communities. Fungal families and OTUs were more evenly distributed in the soil than in roots, probably as a result of soil plowing before the establishment of the plantation. Saprophytic, pathogenic, and endophytic fungi were the dominating groups in soil, whereas ECMs were dominant in roots (87%). Arbuscular mycorrhizal diversity was higher in soil than in roots. Species richness of the root-associated ECM community, which was low compared with ECM fungi detected by 454 analyses, increased after 1 year. This increase was mainly caused by ECM fungal species already traced in the preceding year in roots. This result supports the priority concept that ECMs present on roots have a competitive advantage over soil-localized ECM fungi. PMID:22957194

  17. Soil GHG emissions in a Miscanthus plantation as affected by increasing rates of biochar application.

    NASA Astrophysics Data System (ADS)

    Panzacchi, P.; Davies, C. A.; Ventura, M.; Michie, E. J.; Tonon, G.

    2012-04-01

    Biochar is defined as charcoal produced by pyrolysis with the aim to apply it to the soil in order to improve its fertility and carbon (C) storage capacity. Biochar physical and chemical properties can vary depending on the original biomass feedstock and pyrolysis conditions. The potential agricultural benefits and CO2 carbon sequestration from the application of biochar to soil, were assessed in field trials with well characterised biochar. In May 2010 we applied biochar from Miscanthus biomass produced at 450 °C at 3 different application rates: 10, 25 and 50 tons ha-1 to a 6 year old Miscanthus x giganteus plantation in Brattleby (Lincoln, UK) . Each treated 25 m2 plot had 4 replicates according to a randomised block experimental design. Biochar was incorporated to a depth of 10 cm in the soil between plant rhizomes after the harvest, through shallow tilling. CO2 emissions from biochar amended soil were monitored every two weeks by a portable infrared gas analyser (IRGA) with a closed dynamic chamber system, and continuously through 8 automated chambers (both systems from Li-COR, Lincoln, Nebraska). N2O fluxes were monitored using a closed static chamber technique with manual gas sampling and subsequent gas chromatography. Cation/anion exchange resin lysimeters were buried 20 cm deep in order to capture the leached nitrogen. Higher biochar applications led to a reduction of CO2 effluxes in the first 10 weeks of the experiment, after which no treatment effect was observed. The emission of N2O was significantly reduced in the 25 and 50 tons ha-1 application rates. Addition of biochar had no significant affect on the surface soil temperature, however the temperature sensitivity of soil respiration in the biochar treated plots decreased with increasing application rates

  18. Banana leaf and glucose mineralization and soil organic matter in microhabitats of banana plantations under long-term pesticide use.

    PubMed

    Blume, Elena; Reichert, José Miguel

    2015-06-01

    Soil organic matter (SOM) and microbial activity are key components of soil quality and sustainability. In the humid tropics of Costa Rica 3 pesticide regimes were studied-fungicide (low input); fungicide and herbicide (medium input); and fungicide, herbicide, and nematicide (high input)-under continuous banana cultivation for 5 yr (young) or 20 yr (old) in 3 microhabitats-nematicide ring around plants, litter pile of harvested banana, and bare area between litter pile and nematicide ring. Soil samples were incubated sequentially in the laboratory: unamended, amended with glucose, and amended with ground banana leaves. Soil organic matter varied with microhabitat, being greatest in the litter pile, where microbes had the greatest basal respiration with ground banana leaf, whereas microbes in the nematicide ring had the greatest respiration with glucose. These results suggest that soil microbes adapt to specific microhabitats. Young banana plantations had similar SOM compared with old plantations, but the former had greater basal microbial respiration in unamended and in glucose-amended soil and greater first-order mineralization rates in glucose-amended soil, thus indicating soil biological quality decline over time. High pesticide input did not decrease microbial activity or mineralization rate in surface soil. In conclusion, microbial activity in tropical volcanic soil is highly adaptable to organic and inorganic inputs. PMID:25703385

  19. Fate of spinosad in litter and soils of a white spruce plantation in central Ontario.

    PubMed

    Thompson, Dean G; Harris, Brenda J; Buscarini, Teresa M; Chartrand, Derek T

    2002-04-01

    Spinosad is a natural insecticide with potential as a novel biorational control agent for spruce budworm (Choristoneura fumiferana [Clem]), the most destructive insect defoliator of spruce and balsam fir in Canada. Concurrent terrestrial fate experiments were conducted under full coniferous canopy and in a natural opening of a mature white spruce (Piecea glauca [Moench]) plantation of central Ontario to examine the fate and persistence of spinosad in the forest floor and underlying soils. Mean initial residues of spinosyn A and D were approximately 0.2 and 0.02 microgram g-1, respectively, in thatch and exposed soils, but were substantially higher, 2.72 and 0.36 micrograms g-1, in litter under coniferous canopy. Results demonstrated that spinosad residues in spruce litter, graminaceous thatch and exposed sandy loam soils dissipated rapidly, following hyperbolic or exponential decline models. Dissipation time (DT50) values ranged from 2.0 to 7.8 days, depending on matrix and experimental conditions. Transient increases in demethylated metabolite residues confirmed that the parent product was degraded in situ. No evidence of vertical mobility of any of the analytes was observed. PMID:11975189

  20. Analyzing the impact of climate and management factors on the productivity and soil carbon sequestration of poplar plantations.

    PubMed

    Wang, Dan; Fan, Jiazhi; Jing, Panpan; Cheng, Yong; Ruan, Honghua

    2016-01-01

    It is crucial to investigate how climate and management factors impact poplar plantation production and soil carbon sequestration interactively. We extracted above-ground net primary production (ANPP), climate and management factors from peer-reviewed journal articles and analyzed impact of management factor and climate on the mean annual increment (MAI) of poplar ANPP statistically. Previously validated mechanistic model (ED) is used to perform case simulations for managed poplar plantations under different harvesting rotations. The meta-analysis indicate that the dry matter MAI was 6.3 Mg ha(-1) yr(-1) (n=641, sd=4.9) globally, and 5.1 (n=292, sd=4.0), 8.1 (n=224, sd=4.7) and 4.4 Mg ha(-1) yr(-1) (n=125, sd=3.2) in Europe, the US and China, respectively. Poplar MAI showed a significant response to GDD, precipitation and planting density and formed a quadratic relationship with stand age. The low annual production for poplar globally was probably caused by suboptimal water availability, rotation length and planting density. SEM attributes the variance of poplar growth rate more to climate than to management effects. Case simulations indicated that longer rotation cycle significantly increased soil carbon storage. Findings of this work suggests that management factor of rotation cycle alone could have dramatic impact on the above ground growth, as well as on the soil carbon sequestration of poplar plantations and will be helpful to quantify the long-term carbon sequestration through short rotation plantation. The findings of this study are useful in guiding further research, policy and management decisions towards sustainable poplar plantations. PMID:26531329

  1. Soil greenhouse gas fluxes from a poplar bioenergy plantation: How long does former land use type matter?

    NASA Astrophysics Data System (ADS)

    Görres, Carolyn-Monika; Kammann, Claudia; Ceulemans, Reinhart

    2015-04-01

    The cultivation of fast-growing tree species for the production of bioenergy -- known as short rotation woody crops (SRWC) -- is considered to be carbon-neutral because biomass combustion releases only carbon which has previously been extracted from the atmosphere via photosynthesis. The true greenhouse gas (GHG) mitigation potential of SRWC, however, remains largely unknown due to limited knowledge on the amount of GHG released from the soil during cultivation, and the soil organic carbon (SOC) sequestration rate over time. Especially measurements of the complete GHG balance of SRWC plantations which have already been managed for several years are lacking. The aim of this study was to quantify the spatial and temporal variability of soil GHG fluxes in a SRWC plantation with poplar located in Lochristi, Belgium (POPFULL, http://uahost.uantwerpen.be/popfull/). The plantation has been established in April 2010 partly on former cropland and partly on former pasture, enabling us to study the dependency of soil GHG fluxes on former land use type under identical climate and management conditions. Furthermore, spatial differences in the SOC content created by alternating row spacings between poplars were studied. The plantation was harvested in February 2012, and in February 2014. Soil CO_2, CH_4, N_2O and CO fluxes were simultaneously monitored with automated closed dynamic chamber systems from May 2013 until August 2014, embracing a pre- and post-harvest period. The chamber measurements were accompanied by fortnightly measurements of soil gas concentrations in the top- and subsoil (2013: CO2 and O_2, 2014: CO_2, CH_4, and N_2O). Preliminary results show that former pasture and cropland areas were still distinguishable within the plantation based on properties such as weed composition, dry bulk density and SOC content. During a drought period in August 2013, soil CO2 fluxes seemed to be slightly higher from the former cropland area, but no apparent effect of former land

  2. Soil-plant-atmosphere conditions regulating convective cloud formation above southeastern US pine plantations.

    PubMed

    Manoli, Gabriele; Domec, Jean-Christophe; Novick, Kimberly; Oishi, Andrew Christopher; Noormets, Asko; Marani, Marco; Katul, Gabriel

    2016-06-01

    Loblolly pine trees (Pinus taeda L.) occupy more than 20% of the forested area in the southern United States, represent more than 50% of the standing pine volume in this region, and remove from the atmosphere about 500 g C m-2 per year through net ecosystem exchange. Hence, their significance as a major regional carbon sink can hardly be disputed. What is disputed is whether the proliferation of young plantations replacing old forest in the southern United States will alter key aspects of the hydrologic cycle, including convective rainfall, which is the focus of the present work. Ecosystem fluxes of sensible (Hs) and latent heat (LE) and large-scale, slowly evolving free atmospheric temperature and water vapor content are known to be first-order controls on the formation of convective clouds in the atmospheric boundary layer. These controlling processes are here described by a zero-order analytical model aimed at assessing how plantations of different ages may regulate the persistence and transition of the atmospheric system between cloudy and cloudless conditions. Using the analytical model together with field observations, the roles of ecosystem Hs and LE on convective cloud formation are explored relative to the entrainment of heat and moisture from the free atmosphere. Our results demonstrate that cloudy-cloudless regimes at the land surface are regulated by a nonlinear relation between the Bowen ratio Bo=Hs/LE and root-zone soil water content, suggesting that young/mature pines ecosystems have the ability to recirculate available water (through rainfall predisposition mechanisms). Such nonlinearity was not detected in a much older pine stand, suggesting a higher tolerance to drought but a limited control on boundary layer dynamics. These results enable the generation of hypotheses about the impacts on convective cloud formation driven by afforestation/deforestation and groundwater depletion projected to increase following increased human population in the

  3. Nitrous Oxide Fluxes in Fertilized L. Plantations across a Gradient of Soil Drainage Classes.

    PubMed

    Shrestha, Raj K; Strahm, Brian D; Sucre, Eric B

    2014-11-01

    The effect of fertilizer management on nitrous oxide (NO) fluxes in agricultural ecosystems is well documented; however, our knowledge of these effects in managed forests is minimal. We established a comprehensive research study to address this knowledge gap across a range of soil drainage classes (poorly, moderately, and well drained) common in southern pine plantation management. Fertilizer treatments in each drainage class comprised of control (no fertilizer), urea + phosphorus (P), and P-coated urea fertilizer (CUF). Fertilization (168 kg N ha) occurred independently during the spring, summer, and fall to assess the effects of application timing. Nitrous oxide sampling, using vented static chambers, started immediately after seasonal fertilizer application and was performed every 6 wk for more than 1 yr. Time-integrated net annual NO emissions increased with urea (1.15 kg NO-N ha) and CUF (0.88 kg NO-N ha) application compared with unfertilized control (0.22 kg NO-N ha). Mean annual NO flux was significantly increased with fall fertilization (1.17 kg NO-N ha) relative to spring (0.73 kg NO-N ha) or summer (0.33 kg NO-N ha). Similarly, average annual NO flux was higher in poorly drained soils (1.40 kg NO-N ha) than in moderately drained (0.46 kg NO-N ha) and well-drained soils (0.39 kg NO-N ha). This study suggests that NO emissions after fertilization can be minimized by avoiding fall fertilization and poorly drained soils and by selecting enhanced-efficiency N fertilizers over urea. PMID:25602199

  4. Responses of soil microbial communities and enzyme activities to nitrogen and phosphorus additions in Chinese fir plantations of subtropical China

    NASA Astrophysics Data System (ADS)

    Dong, W. Y.; Zhang, X. Y.; Liu, X. Y.; Fu, X. L.; Chen, F. S.; Wang, H. M.; Sun, X. M.; Wen, X. F.

    2015-09-01

    Nitrogen (N) and phosphorus (P) additions to forest ecosystems are known to influence various above-ground properties, such as plant productivity and composition, and below-ground properties, such as soil nutrient cycling. However, our understanding of how soil microbial communities and their functions respond to nutrient additions in subtropical plantations is still not complete. In this study, we added N and P to Chinese fir plantations in subtropical China to examine how nutrient additions influenced soil microbial community composition and enzyme activities. The results showed that most soil microbial properties were responsive to N and/or P additions, but responses often varied depending on the nutrient added and the quantity added. For instance, there were more than 30 % greater increases in the activities of β-glucosidase (βG) and N-acetyl-β-D-glucosaminidase (NAG) in the treatments that received nutrient additions compared to the control plot, whereas acid phosphatase (aP) activity was always higher (57 and 71 %, respectively) in the P treatment. N and P additions greatly enhanced the phospholipid fatty acids (PLFAs) abundance especially in the N2P (100 kg ha-1 yr-1 of N +50 kg ha-1 yr-1 of P) treatment; the bacterial PLFAs (bacPLFAs), fungal PLFAs (funPLFAs) and actinomycic PLFAs (actPLFAs) were about 2.5, 3 and 4 times higher, respectively, than in the CK (control). Soil enzyme activities were noticeably higher in November than in July, mainly due to seasonal differences in soil moisture content (SMC). βG or NAG activities were significantly and positively correlated with microbial PLFAs. These findings indicate that βG and NAG would be useful tools for assessing the biogeochemical transformation and metabolic activity of soil microbes. We recommend combined additions of N and P fertilizer to promote soil fertility and microbial activity in this kind of plantation.

  5. The effect of surface cover and soil devastation on infiltration rate in steep forest plantations

    NASA Astrophysics Data System (ADS)

    Onda, Y.; Hiraoka, M.; Kato, H.; Gomi, T.; Miyata, S.; Mizugaki, S.

    2008-12-01

    The Japanese cypress (Hinoki; Chamaecyparis obtusa) is a major commercial tree species in Japan, and without thinning of high-density stands, canopy closure prevents development of understory vegetation. Therefore there is a concern for overlandflow and sediment yield due to infiltration rate lowering. We developed a light-weight rainfall simulator based on the design of Meyer and Harmon (1979). A flat fan Veejet 80150 spraying nozzle (Spraying systems Co., USA) is mounted on the manifold at 2.13 m high from the plot surface. The nozzle oscillates so that the spray fan sweeps across the targeting 1 m x 1 m plot. The Veejet 80150 spraying nozzle produces large raindrops larger than 2 mm in diameter, and can simulate the high raindrop kinetic energy of natural throughfall. A targeted rainfall rate is 180 mm/h. About 30 sprinkling experiments have been conducted on 35-degree hillslopes with varying surface cover in 5 locations in Japan. We obtained the minimum infiltration rate of 14 mm/h where the surface cover is very little. The infiltration rates were plotted against the total understory vegetation and dry weight of total surface cover including litter. The infiltration rate increased with the increasing total surface cover, and generally higher regression coefficient was found for the case of the total surface cover. In some cases, high infiltration rates were obtained where surface cover is low. Two possible explanations can be made; 1) surface soil (especially fine particles) has been washed away, where soil is mostly composed of gravel and the percentage of fine fraction is low, or 2) because of long-term soil loss by raindrop detachment, remaining soil looks like "ghanging"h between exposed fine root networks of Japanese cypress, where soil bulk density is significantly lower than other site. Therefore the infiltration rate in the devastated Japanese cypress plantations is not only controlled by loss of surface vegetation by low light condition, but soil

  6. Intensive Eucalyptus plantation management in Brazil: Long-term effects on soil carbon dynamics across 300 sites

    NASA Astrophysics Data System (ADS)

    Cook, R. L.; Stape, J.; Binkley, D.

    2011-12-01

    Intensively managed forest plantations now cover more than 6 million hectares in Brazil, and another 20 million hectares in other tropical regions. Although aboveground biomass, and therefore carbon, is well monitored due to commercial interest, the belowground carbon dynamics and site sustainability remain poorly understood. So, how does intensive silviculture change the storage of carbon in soils? Trends in soil organic carbon from land-use change indicate that conversion from pastures to Eucalyptus plantations should maintain soil carbon stocks. However, comprehensive, long-term studies are needed to understand the variability in these trends to better manage these systems for sustainable productivity across a highly variable landscape, as well as to understand the role that soils may play in sequestering carbon for climate change mitigation. In this unique, long-term soil study, soil samples were collected in the 1980s/90s, 2001, and 2010 across 300 intensively managed Eucalyptus plantation sites located in the states of Bahia, Espirito Santo, and Sao Paulo, Brazil. Natural ecosystems for these states include Savannah-Dry Forest, Atlantic Forest, and Savanna, respectively. The sampling covered at least three complete rotations of Eucalyptus at each site; climate, past land use, productivity, and soil characteristics vary across this geographic gradient. Across the two periods, both Espirito Santo (P<0.001) and Bahia (P=0.05) showed a decrease in soil carbon concentrations, while Sao Paulo saw no change over time. For the 0-30 cm layer, plantations in Espirito Santo state had the largest decrease in soil carbon concentration up to 2001, decreasing soil carbon stocks at an average rate of 1.3 Mg C ha-1 year-1. This, however, was followed by no significant change from 2001 to 2010 which may indicate stabilization of soil carbon stocks under the new land use. The Eucalyptus in Bahia created no change in the first sampling period, but saw a decline of 0.35 Mg C ha-1

  7. Evaluation of soil amendments as a remediation alternative for cadmium-contaminated soils under cacao plantations.

    PubMed

    Chavez, E; He, Z L; Stoffella, P J; Mylavarapu, R; Li, Y; Baligar, V C

    2016-09-01

    Elevated plant-available cadmium (Cd) in soils results in contamination to cacao (Theobroma cacao L) beans. Effectiveness of vermicompost and zeolite in reducing available Cd in three cacao-growing soils was studied under laboratory conditions. Sorption-desorption experiments were conducted in soils and amendments. Cadmium was added at 0 or 5 mg kg(-1) (spiked), then, amendments were incorporated at 0, 0.5, or 2 %. Amended soils were incubated at room temperature for 28 days. Plant-available Cd was determined using 0.01 M CaCl2 (WSE) and Mehlich 3 (M3) extraction procedures in subsamples taken from individual bags at six time intervals. Soils and amendments displayed different sorption characteristics and a better fit was attained with Freundlich model (R (2) > 0.82). Amendments were ineffective in reducing extractable Cd in non-spiked soils. In Cd-spiked soils, vermicompost at 2 % significantly reduced WSE-Cd (P < 0.01) from 3.36, 0.54, and 0.38 mg kg(-1) to values lower that instrument's detection in all the three soils and significantly diminished M3-extractable Cd (P < 0.05) from 4.62 to 4.11 mg kg(-1) in only one soil. Vermicompost at 0.5 % significantly decreased WSE-Cd (P < 0.01) from 3.04 and 0.31 to 1.69 and 0.20 mg kg(-1), respectively, in two soils with low sorption capacity for Cd. In contrast, zeolite failed to reduce WSE- or M3-extractable Cd in all studied soils. A negative correlation occurred between soil pH and WSE-Cd (r > -0.89, P < 0.01). The decrease in WSE-Cd appears to be associated with the increase in pH of the vermicompost-amended soils. PMID:27234831

  8. Carbon Stocks and Soil C Dynamics: an Investigation of C Sequestration Potential in a Eucalyptus grandis Plantation in Hawaii

    NASA Astrophysics Data System (ADS)

    Reeves, M. I.; Crow, S. E.; Yost, R.; Turn, S.

    2011-12-01

    Tropical forests are important for many reasons, one of which is their ability to transfer large quantities of CO2 from the atmosphere to living biomass thereby potentially offsetting climate change. If the biomass is then harvested for commercial use, the stored carbon (C) is released back to the atmosphere. As a result, commercial rotational forestry is generally considered C neutral. However, the growth and harvest of forests also affects the soil C cycle through inputs of below ground biomass in proportion to above ground biomass. With sustainable management practices, soil can be a long-term sink for C, shifting the C balance of the system and providing a climate offset. This study examines the C stocks and dynamics of an E. grandis plantation located in Hawaii. The study has two parts: 1) A snapshot of C resources in the plantation, and 2) An investigation of change in soil C stock and pool size with afforestation. Above ground biomass C was calculated from measurements of the E. grandis trees and ranged from 40-67 Mg C/ha. Below ground biomass C was estimated from published allometric equations and was 16-27 Mg C/ha. 55 preliminary soil cores from 0-30 cm were collected in a 400 m2 plot in the plantation. Strong spatial dependence was observed in a sample variogram constructed from this data, and cumulative organic C in the top 0.4 t ranged from 120-580 Mg C/ha. To identify the effect of E. grandis afforestation on changes in soil C stock and pools, we compared adjacent pastureland and forested plots in a paired design with six sites. The paired plots constrained elevation, climate, and soil series, so that the effects of conversion from pasture to E. grandis plantation could be evaluated. Soil is physically separated into fractions that have different C turnover times: the labile pool which decomposes rapidly, the intermediate (or intra-aggregate) pool which turns over on a decadal scale, and the mineral-associated pool, which can reside in the soil for

  9. Trace elements in soils and plants in temperate forest plantations subjected to single and multiple applications of mixed wood ash.

    PubMed

    Omil, Beatriz; Piñeiro, Verónica; Merino, Agustín

    2007-08-01

    Wood ash, a by-product generated in power plants, can be used to fertilize forest plantations to replenish nutrients lost during harvesting. Although wood ash generally contains low levels of trace metals, release of some of these may occur soon after ash application in acid soils. The risk of heavy metal contamination associated with application of mixed wood ash was assessed in six Pinus radiata D. Don plantations, on two types of mineral soil differing in texture, drainage and CECe. Four of the stands received a single application of 4500 kg ha(-1) (March 2003), and in the other two stands the same treatment was applied over three consecutive years (2003-2005). Trace metal (Cd, Cr, Cu, Mn, Ni, Pb, Zn) concentrations were monitored throughout the 3 years in different components of the forest ecosystem--soil solid fraction, soil solution, tree needles, ground vegetation and different mushroom species. Repeated applications of wood ash led to moderate increases in soil extractable Mn and Zn, and Mn in all mushrooms species. However, the maximum concentrations did not reach levels potentially harmful to organisms. Concentrations of Zn, Cu and Cd decreased in some mushroom species, probably because of increased soil pH caused by the treatment. Heavy metal concentrations in tree needles and ground vegetation were not altered. Although the risk of heavy metal contamination appears to be low, the long-term effects of wood ash application must be assessed. PMID:17499342

  10. Soil organic carbon dynamics of black locust plantations in the middle Loess Plateau area of China

    NASA Astrophysics Data System (ADS)

    Lu, N.; Liski, J.; Chang, R. Y.; Akujärvi, A.; Wu, X.; Jin, T. T.; Wang, Y. F.; Fu, B. J.

    2013-11-01

    Soil organic carbon (SOC) is the largest terrestrial carbon pool and sensitive to land use and cover change; its dynamics are critical for carbon cycling in terrestrial ecosystems and the atmosphere. In this study, we combined a modeling approach and field measurements to examine the temporal dynamics of SOC following afforestation (Robinia pseudoacacia) of former arable land at six sites under different climatic conditions in the Loess Plateau during 1980-2010, where the annual mean precipitation ranging from 450 mm to 600 mm. The results showed that the measured mean SOC increased to levels higher than before afforestation when taking the last measurements (i.e., at age 25 to 30 yr) at all the sites, although it decreased at the wetter sites in the first few years. The accumulation rates of SOC were 1.58 to 6.22% yr-1 in the upper 20 cm and 1.62 to 5.15% yr-1in the upper 40 cm of soil. The simulations reproduced the basic characteristics of measured SOC dynamics, suggesting that litter input and climatic factors (temperature and precipitation) were the major causes for SOC dynamics and the differences among the sites. They explained 88-96, 48-86 and 57-74% of the variations in annual SOC changes at the soil depths of 0-20, 0-40, and 0-100 cm, respectively. Notably, the simulated SOC decreased during the first few years at all the sites, although the magnitudes of decreases were smaller at the drier sites. This suggested that the modeling may be advantageous in capturing SOC changes at finer timescale. The discrepancy between the simulation and measurement was a result of uncertainties in model structure, data input, and sampling design. Our findings indicated that afforestation promoted soil carbon sequestration at the study sites during 1980-2010. Afforestation activities should decrease soil disturbances to reduce carbon release in the early stage. The long-term strategy for carbon fixation capability of the plantations should also consider the climate and site

  11. Impact of soil moisture changes on growing season length at a teak plantation in Northern Thailand

    NASA Astrophysics Data System (ADS)

    Yoshifuji, N.; Kumagai, T.; Tantasirin, C.; Suzuki, M.

    2008-12-01

    Growing season length is an important factor affecting energy, water, and carbon exchange at deciduous forests. However, our understandings about the extent of inter-annual variation in growing season length and its cause of deciduous forests in tropical region are still not enough, though the impact of modification of growing season length is likely to be critical especially in tropical region because of high radiant energy throughout the year. In order to clarify the extent of inter-annual variation in growing season length and its major cause of a teak plantation in Northern Thailand, we monitored radiative transmittance through the canopy and heat-pulse velocities of canopy trees for 7-year period. We found large inter-annual variations in the timings of leaf-out, leaf-fall, and the start and stop of transpiration. As a result, we revealed that the year-to-year variation in the length of canopy duration and transpiration period spanned about 60 days. It was also found that these large year-to-year variations can be explained by the differences in the timings of soil moisture changes caused by the differences in the timings of rainfall occurrence. These results imply a profound potential impact of modification of rainfall regime on canopy-atmosphere water and carbon exchange on annual time scale through the modification of growing season length.

  12. [Effects of the conversion from native shrub forest to Chinese chestnut plantation on soil carbon and nitrogen pools].

    PubMed

    Shang, Su-Yun; Li, Yong-Fu; Jiang, Pei-Kun; Zhou, Guo-Mo; Liu, Juan; Wu, Jia-Sen; Lin, Lin

    2012-03-01

    To investigate the effects of the conversion from native shrub forest (NF) to Chinese chestnut plantation (CP) on the soil carbon (C) and nitrogen (N) pools, soil samples were collected from the adjacent NF and CP in Anji County of Zhejiang Province, with their water-soluble organic C (WSOC), microbial biomass C (MBC), readily oxidizable C (ROC), water-soluble organic N (WSON), and microbial biomass N (MBN) determined. The spectral characteristics of soil organic C were also determined by using nuclear magnetic resonance (NMR) technique. After the conversion from NF to CP, the soil alkalyzable N, available phosphorus, and available potassium contents increased significantly, while the soil WSOC, MBC, ROC, WSON, and MBN were in adverse. The soil organic C in both NF and CP was dominated by alkyl C and O-alkyl C, but the proportions of O-alkyl C and carbonyl C in soil organic C decreased while the proportions of alkyl C and aromatic C as well as the alkyl C/O-alkyl C ratio and the aromaticity of soil organic C all increased significantly after the conversion from NF to CP, indicating that this conversion increased the stability of soil organic C pool significantly. In conclusion, the conversion from NF to CP and the intensive management of CP decreased the contents of soil labile C and soil N but increased the stability of soil C pool significantly. PMID:22720608

  13. [Allelopathic effects of the humus soils from Betula platyphylla and Quercus liaotungensis pure plantations on 9 kinds of common shrubs and herbs].

    PubMed

    Huang, Liang-Jia; Liu, Zeng-wen; Zhu, Bo-Chao; Bing, Yuan-Hao; Zhang, Xiao-Xi; Lü, Chen

    2014-06-01

    The humus soils were collected from Betula platyphylla and Quercus liaotungensis pure plantations and woodless land separately where the site conditions were basically the same, and taken as medium for potting culture test of 9 kinds of shrubs or herbs in plastic greenhouse to assess the allelopathic effects of humus soils of pure plantations on shrubs or herbs. Humus soils from B. platyphylla plantation significantly inhibited the seed germinations of Medicago sativa and Melilotus officinalis, decreased the catalase (CAT) activity of M. officinalis, Coronilla varia, M. sativa and Lespedeza davurica, and improved malondialdehyde (MDA) contents in seedlings of Caragana kor-shinskii, C. varia and Astragalus adsurgens. The biomass growths of C. varia, Amorpha fruticosa, M. sativa, M. officinalis and A. adsurgens in humus soils from B. platyphylla plantation were significantly decreased by 48.2%, 45.1%, 44.3%, 37.3% and 36.0%, respectively. In addition, humus soil of Q. liaotungensis plantation significantly decreased the germination rates of M. sativa and A. adsurgens, the chlorophyll contents of Vicia villosa, A. fruticosa and M. sativa, and improved malondialdehyde (MDA) contents in seedlings of Lespedeza davurica, Caragana korshinskii, M. officinalis and A. adsurgens. The biomass growths of A. adsurgens, M. sativa, M. officinalis and A. fruticosa were significantly decreased by 52.6% , 43.8%, 35.5% and 34.6%, respective- ly. B. platyphylla plantation humus soil had obvious inhibition effects on M. sativa, M. officinalis and A. fruticosa, while Q. liaotungensis plantation humus soil had obvious inhibition effects on M. sativa, A. adsurgens and A. fruticosa. PMID:25223017

  14. Ecosystem carbon balance and vulnerability of soil carbon in a drained lower coastal plain loblolly pine plantation

    NASA Astrophysics Data System (ADS)

    Noormets, A.; McNulty, S. G.; Gavazzi, M.; Domec, J.; Sun, G.; King, J. S.; Chen, J.

    2008-12-01

    Coastal plain ecosystems comprise only about 5% of total U.S. land area, but the soil carbon density in these ecosystems is about 10-fold higher than in upland ecosystems and they may therefore play a disproportionately large role in ecosystem-climate feedbacks. The role of these ecosystems in continental carbon exchange is largely unclear because they have been underrepresented in flux monitoring networks. We monitored ecosystem carbon fluxes and pools for three years in two lower coastal plain loblolly pine plantations (3 and 17 years of age). The contribution of soil to ecosystem respiration decreased from over 90% immediately following a harvest to about 50% by age 17. The replenishment of soil C through litterfall exceeded heterotrophic respiration (Rh) by 2-9% in two years, but was 30% lower than Rh in the third year, highlighting the vulnerability of soil carbon stocks to interannual climate variability.

  15. Effect of Monospecific and Mixed Sea-Buckthorn (Hippophae rhamnoides) Plantations on the Structure and Activity of Soil Microbial Communities

    PubMed Central

    Yu, Xuan; Liu, Xu; Zhao, Zhong; Liu, Jinliang; Zhang, Shunxiang

    2015-01-01

    This study aims to evaluate the effect of different afforestation models on soil microbial composition in the Loess Plateau in China. In particular, we determined soil physicochemical properties, enzyme activities, and microbial community structures in the top 0 cm to 10 cm soil underneath a pure Hippophae rhamnoides (SS) stand and three mixed stands, namely, H. rhamnoides and Robinia pseucdoacacia (SC), H. rhamnoides and Pinus tabulaeformis (SY), and H. rhamnoides and Platycladus orientalis (SB). Results showed that total organic carbon (TOC), total nitrogen, and ammonium (NH4+) contents were higher in SY and SB than in SS. The total microbial biomass, bacterial biomass, and Gram+ biomass of the three mixed stands were significantly higher than those of the pure stand. However, no significant difference was found in fungal biomass. Correlation analysis suggested that soil microbial communities are significantly and positively correlated with some chemical parameters of soil, such as TOC, total phosphorus, total potassium, available phosphorus, NH4+ content, nitrate content (NH3−), and the enzyme activities of urease, peroxidase, and phosphatase. Principal component analysis showed that the microbial community structures of SB and SS could clearly be discriminated from each other and from the others, whereas SY and SC were similar. In conclusion, tree species indirectly but significantly affect soil microbial communities and enzyme activities through soil physicochemical properties. In addition, mixing P. tabulaeformis or P. orientalis in H. rhamnoides plantations is a suitable afforestation model in the Loess Plateau, because of significant positive effects on soil nutrient conditions, microbial community, and enzyme activities over pure plantations. PMID:25658843

  16. Effect of monospecific and mixed sea-buckthorn (Hippophae rhamnoides) plantations on the structure and activity of soil microbial communities.

    PubMed

    Yu, Xuan; Liu, Xu; Zhao, Zhong; Liu, Jinliang; Zhang, Shunxiang

    2015-01-01

    This study aims to evaluate the effect of different afforestation models on soil microbial composition in the Loess Plateau in China. In particular, we determined soil physicochemical properties, enzyme activities, and microbial community structures in the top 0 cm to 10 cm soil underneath a pure Hippophae rhamnoides (SS) stand and three mixed stands, namely, H. rhamnoides and Robinia pseucdoacacia (SC), H. rhamnoides and Pinus tabulaeformis (SY), and H. rhamnoides and Platycladus orientalis (SB). Results showed that total organic carbon (TOC), total nitrogen, and ammonium (NH4(+)) contents were higher in SY and SB than in SS. The total microbial biomass, bacterial biomass, and Gram+ biomass of the three mixed stands were significantly higher than those of the pure stand. However, no significant difference was found in fungal biomass. Correlation analysis suggested that soil microbial communities are significantly and positively correlated with some chemical parameters of soil, such as TOC, total phosphorus, total potassium, available phosphorus, NH4(+) content, nitrate content (NH3(-)), and the enzyme activities of urease, peroxidase, and phosphatase. Principal component analysis showed that the microbial community structures of SB and SS could clearly be discriminated from each other and from the others, whereas SY and SC were similar. In conclusion, tree species indirectly but significantly affect soil microbial communities and enzyme activities through soil physicochemical properties. In addition, mixing P. tabulaeformis or P. orientalis in H. rhamnoides plantations is a suitable afforestation model in the Loess Plateau, because of significant positive effects on soil nutrient conditions, microbial community, and enzyme activities over pure plantations. PMID:25658843

  17. [Responses of rhizosphere nitrogen and phosphorus transformations to different acid rain intensities in a hilly red soil tea plantation].

    PubMed

    Chen, Xi; Chen, Fu-sheng; Ye, Su-qiong; Yu, Su-qin; Fang, Xiang-min; Hu, Xiao-fei

    2015-01-01

    Tea (Camellia sinensis) plantation in hilly red soil region has been long impacted by acid deposition, however its effects on nitrogen (N) and phosphorus (P) transformations in rhizosphere soils remain unclear. A 25-year old tea plantation in a typical hilly red soil region was selected for an in situ simulation experiment treated by pH 4.5, pH 3.5, pH 2.5 and control. Rhizosihere and bulk soils were collected in the third year from the simulated acid deposition experiment. Soil mineral N, available P contents and major enzyme activities were analyzed using the chemical extraction and biochemical methods, and N and P mineralization rates were estimated using the indoor aerobic incubation methods. Our results showed that compared to the control, the treatments of pH 4.5, pH 3.5 and pH 2.5, respectively decreased 7.1%, 42.1% and 49.9% NO3(-)-N, 6.4%, 35.9% and 40.3% mineral N, 10.5%, 41.1% and 46.9% available P, 18.7%, 30.1% and 44.7% ammonification rate, 3.6%, 12.7% and 38.8% net N-mineralization rate, and 31.5%, 41.8% and 63.0% P mineralization rate in rhizosphere soils; however, among the 4 treatments, rhizosphere soil nitrification rate was not significantly different, the rhizosphere soil urease and acid phosphatase activities generally increased with the increasing intensity of acid rain (P<0.05). In bulk soil, compared with the control, the treatments of pH 4.5, pH 3.5 and pH 2.5 did not cause significant changes in NO3(-)-N, mineral N, available P as well as in the rates of nitrification, ammonification, net N-mineralization and P mineralization. With increasing the acid intensity, the rhizosphere effects of NH4+-N, NO3(-)-N, mineral N, ammonification and net N-mineralization rates were altered from positive to negative effects, those of urease and acid phosphatease showed the opposite trends, those of available P and P mineralization were negative and that of nitrification was positive. In sum, prolonged elevated acid rain could reduce N and P transformation

  18. Effects of Manipulated Above- and Belowground Organic Matter Input on Soil Respiration in a Chinese Pine Plantation

    PubMed Central

    Zhao, Bo; Wu, Lianhai; Zhang, Chunyu; Zhao, Xiuhai; Gadow, Klaus v.

    2015-01-01

    Alteration in the amount of soil organic matter input can have profound effect on carbon dynamics in forest soils. The objective of our research was to determine the response in soil respiration to above- and belowground organic matter manipulation in a Chinese pine (Pinus tabulaeformis) plantation. Five organic matter treatments were applied during a 2-year experiment: both litter removal and root trenching (LRRT), only litter removal (LR), control (CK), only root trenching (RT) and litter addition (LA). We found that either aboveground litter removal or root trenching decreased soil respiration. On average, soil respiration rate was significantly decreased in the LRRT treatment, by about 38.93% ± 2.01% compared to the control. Soil respiration rate in the LR treatment was 30.65% ± 1.87% and in the RT treatment 17.65% ± 1.95% lower than in the control. Litter addition significantly increased soil respiration rate by about 25.82% ± 2.44% compared to the control. Soil temperature and soil moisture were the main factors affecting seasonal variation in soil respiration. Up to the 59.7% to 82.9% seasonal variation in soil respiration is explained by integrating soil temperature and soil moisture within each of the various organic matter treatments. The temperature sensitivity parameter, Q10, was higher in the RT (2.72) and LA (3.19) treatments relative to the control (2.51), but lower in the LRRT (1.52) and LR treatments (1.36). Our data suggest that manipulation of soil organic matter input can not only alter soil CO2 efflux, but also have profound effect on the temperature sensitivity of organic carbon decomposition in a temperate pine forest. PMID:25970791

  19. Effects of manipulated above- and belowground organic matter input on soil respiration in a Chinese pine plantation.

    PubMed

    Fan, Juan; Wang, Jinsong; Zhao, Bo; Wu, Lianhai; Zhang, Chunyu; Zhao, Xiuhai; Gadow, Klaus V

    2015-01-01

    Alteration in the amount of soil organic matter input can have profound effect on carbon dynamics in forest soils. The objective of our research was to determine the response in soil respiration to above- and belowground organic matter manipulation in a Chinese pine (Pinus tabulaeformis) plantation. Five organic matter treatments were applied during a 2-year experiment: both litter removal and root trenching (LRRT), only litter removal (LR), control (CK), only root trenching (RT) and litter addition (LA). We found that either aboveground litter removal or root trenching decreased soil respiration. On average, soil respiration rate was significantly decreased in the LRRT treatment, by about 38.93% ± 2.01% compared to the control. Soil respiration rate in the LR treatment was 30.65% ± 1.87% and in the RT treatment 17.65% ± 1.95% lower than in the control. Litter addition significantly increased soil respiration rate by about 25.82% ± 2.44% compared to the control. Soil temperature and soil moisture were the main factors affecting seasonal variation in soil respiration. Up to the 59.7% to 82.9% seasonal variation in soil respiration is explained by integrating soil temperature and soil moisture within each of the various organic matter treatments. The temperature sensitivity parameter, Q10, was higher in the RT (2.72) and LA (3.19) treatments relative to the control (2.51), but lower in the LRRT (1.52) and LR treatments (1.36). Our data suggest that manipulation of soil organic matter input can not only alter soil CO2 efflux, but also have profound effect on the temperature sensitivity of organic carbon decomposition in a temperate pine forest. PMID:25970791

  20. Fertilizer regime impacts on abundance and diversity of soil fauna across a poplar plantation chronosequence in coastal Eastern China.

    PubMed

    Wang, Shaojun; Chen, Han Y H; Tan, Yan; Fan, Huan; Ruan, Honghua

    2016-01-01

    Soil fauna are critical for ecosystem function and sensitive to the changes of soil fertility. The effects of fertilization on soil fauna communities, however, remain poorly understood. We examined the effects of fertilization form and quantity on the abundance, diversity and composition of soil fauna across an age-sequence of poplar plantations (i.e., 4-, 9- and 20-yr-old) in the coastal region of eastern China. We found that the effects of fertilization on faunal abundance, diversity, and composition differed among stand ages. Organic fertilizers increased the total abundance of soil fauna, whereas low level inorganic fertilizers imparted increases only in the 4- and 9-yr-old stands. The number of faunal groups did not change with fertilization, but Shannon's and Margalef diversity indices increased under low level organic fertilization, and decreased under inorganic fertilization in the 9- and 20-yr-old stands. Community composition of soil fauna differed strongly with fertilization and stand age. The changes in soil fauna were strongly associated with the changes in microbial biomass carbon, dissolved organic carbon and nitrogen, and available phosphorus and potassium. Our findings suggest that the responses of soil fauna to fertilization may be mediated through the fertilization effects on soil nutrient availability. PMID:26857390

  1. Fertilizer regime impacts on abundance and diversity of soil fauna across a poplar plantation chronosequence in coastal Eastern China

    PubMed Central

    Wang, Shaojun; Chen, Han Y. H.; Tan, Yan; Fan, Huan; Ruan, Honghua

    2016-01-01

    Soil fauna are critical for ecosystem function and sensitive to the changes of soil fertility. The effects of fertilization on soil fauna communities, however, remain poorly understood. We examined the effects of fertilization form and quantity on the abundance, diversity and composition of soil fauna across an age-sequence of poplar plantations (i.e., 4-, 9- and 20-yr-old) in the coastal region of eastern China. We found that the effects of fertilization on faunal abundance, diversity, and composition differed among stand ages. Organic fertilizers increased the total abundance of soil fauna, whereas low level inorganic fertilizers imparted increases only in the 4- and 9-yr-old stands. The number of faunal groups did not change with fertilization, but Shannon’s and Margalef diversity indices increased under low level organic fertilization, and decreased under inorganic fertilization in the 9- and 20-yr-old stands. Community composition of soil fauna differed strongly with fertilization and stand age. The changes in soil fauna were strongly associated with the changes in microbial biomass carbon, dissolved organic carbon and nitrogen, and available phosphorus and potassium. Our findings suggest that the responses of soil fauna to fertilization may be mediated through the fertilization effects on soil nutrient availability. PMID:26857390

  2. Investigating plantation-induced near-surface soil hydrophobicity and its impact on groundwater recharge in the Nebraska Sand Hills, USA

    NASA Astrophysics Data System (ADS)

    Adane, Z. A.; Nasta, P.; Gates, J. B.

    2014-12-01

    Although numerous studies in diverse environmental settings have demonstrated that plantations tend to reduce soil moisture and recharge rates, research on physical mechanisms affecting these linkages tend to focus mainly on the effects of evapotranspiration and interception. This study investigates the extent of soil hydrophobicity resulting from land use changes and its impact on groundwater recharge in a century-old experimental forest surrounded by grassland in the Northern High Plains (Nebraska National Forest). Water Drop Penetration Tests (WDPT) and Nuclear Magnetic Resonance (NMR) spectroscopy were used to investigate soil hydrophobicity on 50 cm soil cores collected from experimental plots beneath 5 land cover types. WDPT analysis indicated that most near-surface soils (0-12.5 and 12.5-25 cm) beneath pine plots were moderately to strongly hydrophobic. NMR spectroscopy analysis comparing ratios of hydrophobic (3.2-0.5 and 8.5-6.5 ppm) to hydrophilic (6.5-3.2 ppm) regions suggests that surface soils beneath the plantations were uniformly more hydrophobic than grasslands (by ~30 to 260%). Unsaturated zone soil cores were collected from beneath each experimental plot for comparison of hydrophobicity with recharge rates based on chloride and sulfate mass balance. Recharge estimates beneath the plantations (4-10 mm yr-1) represent reductions of 86-94% relative to the surrounding native grassland, suggesting a link between soil hydrophobicity and reduced infiltration beneath the plantations.

  3. Conversion of lowland tropical forests to tree cash crop plantations loses up to one-half of stored soil organic carbon.

    PubMed

    van Straaten, Oliver; Corre, Marife D; Wolf, Katrin; Tchienkoua, Martin; Cuellar, Eloy; Matthews, Robin B; Veldkamp, Edzo

    2015-08-11

    Tropical deforestation for the establishment of tree cash crop plantations causes significant alterations to soil organic carbon (SOC) dynamics. Despite this recognition, the current Intergovernmental Panel on Climate Change (IPCC) tier 1 method has a SOC change factor of 1 (no SOC loss) for conversion of forests to perennial tree crops, because of scarcity of SOC data. In this pantropic study, conducted in active deforestation regions of Indonesia, Cameroon, and Peru, we quantified the impact of forest conversion to oil palm (Elaeis guineensis), rubber (Hevea brasiliensis), and cacao (Theobroma cacao) agroforestry plantations on SOC stocks within 3-m depth in deeply weathered mineral soils. We also investigated the underlying biophysical controls regulating SOC stock changes. Using a space-for-time substitution approach, we compared SOC stocks from paired forests (n = 32) and adjacent plantations (n = 54). Our study showed that deforestation for tree plantations decreased SOC stocks by up to 50%. The key variable that predicted SOC changes across plantations was the amount of SOC present in the forest before conversion--the higher the initial SOC, the higher the loss. Decreases in SOC stocks were most pronounced in the topsoil, although older plantations showed considerable SOC losses below 1-m depth. Our results suggest that (i) the IPCC tier 1 method should be revised from its current SOC change factor of 1 to 0.6 ± 0.1 for oil palm and cacao agroforestry plantations and 0.8 ± 0.3 for rubber plantations in the humid tropics; and (ii) land use management policies should protect natural forests on carbon-rich mineral soils to minimize SOC losses. PMID:26217000

  4. Conversion of lowland tropical forests to tree cash crop plantations loses up to one-half of stored soil organic carbon

    PubMed Central

    van Straaten, Oliver; Corre, Marife D.; Wolf, Katrin; Tchienkoua, Martin; Cuellar, Eloy; Matthews, Robin B.; Veldkamp, Edzo

    2015-01-01

    Tropical deforestation for the establishment of tree cash crop plantations causes significant alterations to soil organic carbon (SOC) dynamics. Despite this recognition, the current Intergovernmental Panel on Climate Change (IPCC) tier 1 method has a SOC change factor of 1 (no SOC loss) for conversion of forests to perennial tree crops, because of scarcity of SOC data. In this pantropic study, conducted in active deforestation regions of Indonesia, Cameroon, and Peru, we quantified the impact of forest conversion to oil palm (Elaeis guineensis), rubber (Hevea brasiliensis), and cacao (Theobroma cacao) agroforestry plantations on SOC stocks within 3-m depth in deeply weathered mineral soils. We also investigated the underlying biophysical controls regulating SOC stock changes. Using a space-for-time substitution approach, we compared SOC stocks from paired forests (n = 32) and adjacent plantations (n = 54). Our study showed that deforestation for tree plantations decreased SOC stocks by up to 50%. The key variable that predicted SOC changes across plantations was the amount of SOC present in the forest before conversion—the higher the initial SOC, the higher the loss. Decreases in SOC stocks were most pronounced in the topsoil, although older plantations showed considerable SOC losses below 1-m depth. Our results suggest that (i) the IPCC tier 1 method should be revised from its current SOC change factor of 1 to 0.6 ± 0.1 for oil palm and cacao agroforestry plantations and 0.8 ± 0.3 for rubber plantations in the humid tropics; and (ii) land use management policies should protect natural forests on carbon-rich mineral soils to minimize SOC losses. PMID:26217000

  5. Impact of interspecific interactions on the soil water uptake depth in a young temperate mixed species plantation

    NASA Astrophysics Data System (ADS)

    Grossiord, Charlotte; Gessler, Arthur; Granier, André; Berger, Sigrid; Bréchet, Claude; Hentschel, Rainer; Hommel, Robert; Scherer-Lorenzen, Michael; Bonal, Damien

    2014-11-01

    Interactions between tree species in forests can be beneficial to ecosystem functions and services related to the carbon and water cycles by improving for example transpiration and productivity. However, little is known on below- and above-ground processes leading to these positive effects. We tested whether stratification in soil water uptake depth occurred between four tree species in a 10-year-old temperate mixed species plantation during a dry summer. We selected dominant and co-dominant trees of European beech, Sessile oak, Douglas fir and Norway spruce in areas with varying species diversity, competition intensity, and where different plant functional types (broadleaf vs. conifer) were present. We applied a deuterium labelling approach that consisted of spraying labelled water to the soil surface to create a strong vertical gradient of the deuterium isotope composition in the soil water. The deuterium isotope composition of both the xylem sap and the soil water was measured before labelling, and then again three days after labelling, to estimate the soil water uptake depth using a simple modelling approach. We also sampled leaves and needles from selected trees to measure their carbon isotope composition (a proxy for water use efficiency) and total nitrogen content. At the end of the summer, we found differences in the soil water uptake depth between plant functional types but not within types: on average, coniferous species extracted water from deeper layers than did broadleaved species. Neither species diversity nor competition intensity had a detectable influence on soil water uptake depth, foliar water use efficiency or foliar nitrogen concentration in the species studied. However, when coexisting with an increasing proportion of conifers, beech extracted water from progressively deeper soil layers. We conclude that complementarity for water uptake could occur in this 10-year-old plantation because of inherent differences among functional groups (conifers

  6. Effect of fertilizer and water content on N2O emission from three plantation soils in south China.

    PubMed

    Li, Zhi-an; Zou, Bi; Xia, Han-ping; Ding, Yong-zhen; Tan, Wan-neng; Ma, Zhen-rong

    2005-01-01

    The effects of fertilizers and water content on N2O emission were studied using the three most typical plantation soils. Soil incubations were performed and fertilization and water content treatments were designed. At 25% of saturated water content(SWC), N2O emissions from the soil treated with urea, KNO3, (NH4)2 SO4 and KH2 PO4 were compared at application rates of 0, 100, 200, 300 and 500 kg/hm2. At 80% of SWC, similar experiments were carried out but at only one application rate(500 kg/hm2). N2O emissions at various water contents(20%, 35%, 50%, 65%, 80% and 100% of SWC) were studied. At low water content(25% of SWC), neither nitrogen nor phosphorus(or potassium) fertilizers led to a high level of N2O emission, which generally ranged from 2.03 to 29.02 microg/(m2 x h). However, at high water content(80% SWC), the fertilizers resulted in much greater N2O emission irregardless of soil tested. The highest N2O emission rates after 24 h of water addition were 1233 microg/(m2 x h) for S. superba soil, 1507 microg/(m2 x h) for P. elliottii soil and 1869 microg/ (m2 x h) for A. mangium soil respectively. N2O emission from soils treated with urea, (NH4)2 SO4 and KH2 PO4 immediately dropped to a low level but steadily increased to a very high level for the soil treated with KNO3. High NO3- content was a basis of high level of N2O emission. N2O emission rates from soils peaked shortly after flooding, rapidly dropping to a very low level in soil from non-legume plantations, but lasting for a relatively long period in soil from legume plantations. When soil water content increased equaling to or higher than 65%, the accumulated N2O emission over a period of 13 d ranged from 20.21-29.78 mg/m2 for S. superba, 30.57-70.12 mg/m2 for P. elliottii and 300.89-430.51 mg/m2 for A. mangium. The critical water content was 50% of SWC, above which a high level of N2O emission could be expected, and below which very little N2O emissions were detected. The results suggest that, at low

  7. Phosphorus applications improved the soil microbial responses under nitrogen additions in Chinese fir plantations of subtropical China

    NASA Astrophysics Data System (ADS)

    Zhang, Xinyu; Li, Dandan; Yang, Yang; Tang, Yuqian; Wang, Huimin; Chen, Fusheng; Sun, Xiaomin

    2016-04-01

    Nitrogen (N) deposition and low soil phosphorus (P) content aggravate the P limitation in subtropical forest soils. However, the responses of soil microbial communities, enzyme kinetics, and N cycling genes to P additions in subtropical plantations are still not clear. The hypothesis that P application can alleviate the limitation and improve the soil microbial properties was tested by long term field experiment in the Chinese fir plantations in subtropical China. Thirty 20m×20m plots were established in November 2011 and six different treatments were randomly distributed with five replicates. The treatments are control (CK, no N and P application), low N addition (N1: 50 kg N ha-1 yr-1), high N addition (N2: 100 kg N ha-1 yr-1), P addition (P: 50 kg P ha-1 yr-1), low N and P addition (N1P: 50 kg N ha-1 yr-1 and 50 kg P ha-1 yr-1) and high N and P addition (N2P: 100 kg N ha-1 yr-1 and 50 kg P ha-1 yr-1). A suite of responses of soil microorganism across four years (2012-2015) during three seasons (spring, summer and autumn) were measured. Following 4 years of N amendments, fertilized soils were more acidic and had lower soil microbial biomass carbon contents than CK. However, P alleviated the soil acidification and increased the soil microbial biomass carbon contents. Increases in microbial PLFA biomarkers and exoenzyme kinetics in N fertilized plots were observed in the initial year (2013) but reduced since then (2014 and 2015). Whereas P amendments increased the soil PLFA biomarkers and exoenzyme kinetics through the four years except that the acid phosphatase activities declined after 3 years applications. P applications enhanced the soil N cycling by increases the abundances of nitrifiers (ammonia-oxidizing archea) and denitrifiers (nos Z, norG, and nirK). The bacterial and fungal residue carbons (calculated by amino sugar indicators) were higher under NP fertilizations than the other treatments. Our results suggest that P application could improve the soil

  8. [Soil enzyme activities in a Pleioblastus amurus plantation in Rainy Area of West China under simulated nitrogen deposition].

    PubMed

    Tu, Li-hua; Hu, Ting-xing; Zhang, Jian; Li, Ren-hong; Dai, Hong-zhong; Luo, Shou-hua; Xiang, Yuan-bin; Huang, Li-hua

    2009-12-01

    From November 2007 to May 2009, a simulation test was conducted in a Pleioblastus amarus plantation in Rainy Area of West China to study the effects of nitrogen deposition on the activities of soil enzymes. Four treatments were installed, i.e., control (0 g N x m(-2) x a(-1)), low nitrogen (5 g N x m(-2) x a(-1)), medium nitrogen (15 g N x m(-2) x a(-1)), and high nitrogen (30 g N x m(-2) x a(-1)). Half year after N deposition, 0-20 cm soil samples were collected monthly, and the activities of peroxidase, polyphenol oxidase, cellulase, sucrase, urease, and acid phosphatase were determined. All test enzyme activities had apparent, seasonal variation, with the peak of cellulase, suerase, and acid phosphatase activities in spring, of urease activity in autumn, and of peroxidase and polyphenol oxidase activities in winter. Nitrogen deposition stimulated the activities of polyphenol oxidase, sucrase, urease, and acid phosphatase, inhibited cellulase activity, but had no significant effects on peroxidase activity. The test P. amurus plantation ecosystem was N-limited, and nitrogen deposition stimulated the decomposition of soil organic matter by microbe-enzyme system. PMID:20353060

  9. Water withdrawal in deep soil layers: a key strategy to cope with drought in tropical eucalypt plantations

    NASA Astrophysics Data System (ADS)

    Christina, M.; Laclau, J.; Nouvellon, Y.; Duursma, R. A.; Stape, J. L.; Lambais, G. R.; Le Maire, G.

    2013-12-01

    Little is known about the role of very deep roots to supply the water requirements of tropical forests. Clonal Eucalyptus plantations managed in short rotation on very deep Ferralsols are simple forest ecosystems (only 1 plant genotype growing on a relatively homogeneous soil) likely to provide an insight into tree water use strategies in tropical forests. Fine roots have been observed down to a depth of 6 m at age 1 year in Brazilian eucalypt plantations. However, the contribution of water stored in very deep soil layers to stand evapotranspiration over tree growth has been poorly quantified. An eco-physiological model, MAESPA, has been used to simulate half-hourly stand water balance over the first three years of growth in a clonal Eucalyptus grandis plantation in southern Brazil (Eucflux project, State of São Paulo). The water balance model in MAESPA is an equilibrium-type model between soil and leaf water potentials for individual trees aboveground, and at the stand scale belowground. The dynamics of the vertical fine root distribution have been taken into account empirically from linear interpolations between successive measurements. The simulations were compared to time series of soil water contents measured every meter down to 10m deep and to daily latent heat fluxes measured by eddy covariance. Simulations of volumetric soil water contents matched satisfactorily with measurements (RMSE = 0.01) over the three-year period. Good agreement was also observed between simulated and measured latent heat fluxes. In the rainy season, more than 75 % of tree transpiration was supplied by water withdrawn in the upper 1 m of soil, but water uptake progressed to deeper soil layers during dry periods, down to a depth of 6 m, 12 m and 15 m the first, second and third year after planting, respectively. During the second growing season, 15% of water was withdrawn below a depth of 6 m, and 5% below 10m. Most of the soil down to 12m deep was dried out the second year after

  10. Soil Nitrogen-Cycling Responses to Conversion of Lowland Forests to Oil Palm and Rubber Plantations in Sumatra, Indonesia.

    PubMed

    Allen, Kara; Corre, Marife D; Tjoa, Aiyen; Veldkamp, Edzo

    2015-01-01

    Rapid deforestation in Sumatra, Indonesia is presently occurring due to the expansion of palm oil and rubber production, fueled by an increasing global demand. Our study aimed to assess changes in soil-N cycling rates with conversion of forest to oil palm (Elaeis guineensis) and rubber (Hevea brasiliensis) plantations. In Jambi Province, Sumatra, Indonesia, we selected two soil landscapes - loam and clay Acrisol soils - each with four land-use types: lowland forest and forest with regenerating rubber (hereafter, "jungle rubber") as reference land uses, and rubber and oil palm as converted land uses. Gross soil-N cycling rates were measured using the 15N pool dilution technique with in-situ incubation of soil cores. In the loam Acrisol soil, where fertility was low, microbial biomass, gross N mineralization and NH4+ immobilization were also low and no significant changes were detected with land-use conversion. The clay Acrisol soil which had higher initial fertility based on the reference land uses (i.e. higher pH, organic C, total N, effective cation exchange capacity (ECEC) and base saturation) (P≤0.05-0.09) had larger microbial biomass and NH4+ transformation rates (P≤0.05) compared to the loam Acrisol soil. Conversion of forest and jungle rubber to rubber and oil palm in the clay Acrisol soil decreased soil fertility which, in turn, reduced microbial biomass and consequently decreased NH4+ transformation rates (P≤0.05-0.09). This was further attested by the correlation of gross N mineralization and microbial biomass N with ECEC, organic C, total N (R=0.51-0. 76; P≤0.05) and C:N ratio (R=-0.71 - -0.75, P≤0.05). Our findings suggest that the larger the initial soil fertility and N availability, the larger the reductions upon land-use conversion. Because soil N availability was dependent on microbial biomass, management practices in converted oil palm and rubber plantations should focus on enriching microbial biomass. PMID:26222690

  11. Activity and abundance of methane-oxidizing bacteria in secondary forest and manioc plantations of Amazonian Dark Earth and their adjacent soils.

    PubMed

    Lima, Amanda B; Muniz, Aleksander W; Dumont, Marc G

    2014-01-01

    The oxidation of atmospheric CH4 in upland soils is mostly mediated by uncultivated groups of microorganisms that have been identified solely by molecular markers, such as the sequence of the pmoA gene encoding the β-subunit of the particulate methane monooxygenase enzyme. The objective of this work was to compare the activity and diversity of methanotrophs in Amazonian Dark Earth soil (ADE, Hortic Anthrosol) and their adjacent non-anthropic soil. Secondly, the effect of land use in the form of manioc cultivation was examined by comparing secondary forest and plantation soils. CH4 oxidation potentials were measured and the structure of the methanotroph communities assessed by quantitative PCR (qPCR) and amplicon pyrosequencing of pmoA genes. The oxidation potentials at low CH4 concentrations (10 ppm of volume) were relatively high in all the secondary forest sites of both ADE and adjacent soils. CH4 oxidation by the ADE soil only recently converted to a manioc plantation was also relatively high. In contrast, both the adjacent soils used for manioc cultivation and the ADE soil with a long history of agriculture displayed lower CH4 uptake rates. Amplicon pyrosequencing of pmoA genes indicated that USCα, Methylocystis and the tropical upland soil cluster (TUSC) were the dominant groups depending on the site. By qPCR analysis it was found that USCα pmoA genes, which are believed to belong to atmospheric CH4 oxidizers, were more abundant in ADE than adjacent soil. USCα pmoA genes were abundant in both forested and cultivated ADE soil, but were below the qPCR detection limit in manioc plantations of adjacent soil. The results indicate that ADE soils can harbor high abundances of atmospheric CH4 oxidizers and are potential CH4 sinks, but as in other upland soils this activity can be inhibited by the conversion of forest to agricultural plantations. PMID:25374565

  12. Activity and abundance of methane-oxidizing bacteria in secondary forest and manioc plantations of Amazonian Dark Earth and their adjacent soils

    PubMed Central

    Lima, Amanda B.; Muniz, Aleksander W.; Dumont, Marc G.

    2014-01-01

    The oxidation of atmospheric CH4 in upland soils is mostly mediated by uncultivated groups of microorganisms that have been identified solely by molecular markers, such as the sequence of the pmoA gene encoding the β-subunit of the particulate methane monooxygenase enzyme. The objective of this work was to compare the activity and diversity of methanotrophs in Amazonian Dark Earth soil (ADE, Hortic Anthrosol) and their adjacent non-anthropic soil. Secondly, the effect of land use in the form of manioc cultivation was examined by comparing secondary forest and plantation soils. CH4 oxidation potentials were measured and the structure of the methanotroph communities assessed by quantitative PCR (qPCR) and amplicon pyrosequencing of pmoA genes. The oxidation potentials at low CH4 concentrations (10 ppm of volume) were relatively high in all the secondary forest sites of both ADE and adjacent soils. CH4 oxidation by the ADE soil only recently converted to a manioc plantation was also relatively high. In contrast, both the adjacent soils used for manioc cultivation and the ADE soil with a long history of agriculture displayed lower CH4 uptake rates. Amplicon pyrosequencing of pmoA genes indicated that USCα, Methylocystis and the tropical upland soil cluster (TUSC) were the dominant groups depending on the site. By qPCR analysis it was found that USCα pmoA genes, which are believed to belong to atmospheric CH4 oxidizers, were more abundant in ADE than adjacent soil. USCα pmoA genes were abundant in both forested and cultivated ADE soil, but were below the qPCR detection limit in manioc plantations of adjacent soil. The results indicate that ADE soils can harbor high abundances of atmospheric CH4 oxidizers and are potential CH4 sinks, but as in other upland soils this activity can be inhibited by the conversion of forest to agricultural plantations. PMID:25374565

  13. Carbon Stocks and Soil C Dynamics: an Investigation of C Sequestration Potential in a Eucalyptus grandis Plantation in Hawaii

    NASA Astrophysics Data System (ADS)

    Reeves, M. I.; Crow, S. E.; Yost, R.; Turn, S.

    2012-12-01

    Tropical forests are important for many reasons, one of which is their ability to transfer large quantities of CO2 from the atmosphere to living biomass thereby potentially offsetting climate change. If the biomass is then harvested for commercial use, the stored carbon (C) is released back to the atmosphere and as a result, rotational forestry is generally considered C neutral. However, the growth and harvest of forests also affects the soil C cycle through inputs of below ground biomass (BG) in proportion to above ground biomass (ABG). With sustainable management practices, soil can be a long-term sink for C, and provide a climate offset. This study examines the C stocks and dynamics of a E. grandis plantation located in Hawaii. There are two parts: 1) A snapshot of C resources in the plantation, including live biomass C (both BG and ABG) as well as soil C stock, and 2) An investigation of change in soil C stock and pool size with afforestation in E. grandis plantation. ABG C was calculated using published allometric equations and from measurements of the E. grandis trees and ranged from 41-68 Mg C/ha, while BG C ranged from 7-12 Mg C/ha. Added together, the biomass C stocks constitute a mere ≈10% of the soil C stock. To identify the effect of E. grandis afforestation on changes in soil C stock and pools, we compared adjacent pastureland and forested plots in a paired design. Soil C stocks were measured by taking five 1m soil cores in each of the plots. In the pasture, soil C ranged from 431-723 Mg C/ha, while in the E. grandis, it ranged from 544-692 Mg C/ha, an average percent change of 16%. In all plots, soil C decreased by depth. As expected, the surface (0-18) cm cores in the pasture contained more C on average, as grasses tend to input larger amounts of root biomass C in the surface soil. However, in the 20-70 cm depth, the E. grandis plots contained 20-30% more soil C. It is hypothesized that this is due to large differences in rooting depth. The greater

  14. Deep Soil Carbon Influenced Following Forest Organic Matter Manipulation In A Loblolly Pine Plantation In The Southeastern United States

    NASA Astrophysics Data System (ADS)

    Hatten, J. A.; Mack, J.; Sucre, E.; Leggett, Z.; Roberts, S.; Dewey, J.

    2013-12-01

    Forest harvest residues and forest floor materials are significant sources of mineral soil organic matter and nutrients for regenerating and establishing forests. Harvest residues in particular are occasionally removed, piled, or burned following harvesting. Weyerhaeuser Company established an experimental study to evaluate the effect of the removal and addition of harvest residual and forest-floor on site productivity and soil carbon. This study was installed in a loblolly pine plantation near Millport, Alabama, USA on the Upper Gulf Coastal Plain to test both extremes from complete removal of harvest residues and forest floor to doubling of these materials. This study has been continuously monitored since its establishment in 1994. We have examined the effects of varying forest floor levels on the biomass, soil carbon content, and soil carbon composition in the context of these management activities. Above- and below-ground productivity, soil moisture, soil temperature, and nutrient dynamics have been related to soil organic carbon in mineral soil, size/density fractionation, and lignin and cutin biomarkers from the cupric oxide (CuO)-oxidation technique. We have found that while removing litter and harvest residues has little effect on biomass production and soil carbon, importing litter and harvest residues increases forest productivity and soil carbon content. Interestingly, increased carbon was observed in all depths assessed (O horizon, 0-20, 20-40, and 40-60cm) suggesting that this practice may sequester organic carbon in deep soil horizons. Our biomarker analysis indicated that importing litter and harvest residues increased relative contributions from above ground sources at the 20-40cm depth and increased relative contributions from belowground sources at the 40-60cm depth. These results suggest that organic matter manipulations in managed forests can have significant effects on deep soil carbon that may be resistant to mineralization or the effects of

  15. Soil fertility controls soil-atmosphere carbon dioxide and methane fluxes in a tropical landscape converted from lowland forest to rubber and oil palm plantations

    NASA Astrophysics Data System (ADS)

    Hassler, E.; Corre, M. D.; Tjoa, A.; Damris, M.; Utami, S. R.; Veldkamp, E.

    2015-06-01

    Expansion of palm oil and rubber production, for which global demand is increasing, causes rapid deforestation in Sumatra, Indonesia and is expected to continue in the next decades. Our study aimed to (1) quantify changes in soil CO2 and CH4 fluxes with land-use change, and (2) determine their controlling factors. In Jambi Province, Sumatra, we selected two landscapes on heavily weathered soils that differ mainly in texture: loam and clay Acrisol soils. At each landscape, we investigated the reference land uses: forest and secondary forest with regenerating rubber, and the converted land uses: rubber (7-17 years old) and oil palm plantations (9-16 years old). We measured soil CO2 and CH4 fluxes monthly from December 2012 to December 2013. Annual soil CO2 fluxes from the reference land uses were correlated with soil fertility: low extractable phosphorus (P) coincided with high annual CO2 fluxes from the loam Acrisol soil that had lower fertility than the clay Acrisol soil (P < 0.05). Soil CO2 fluxes from the oil palm decreased compared to the other land uses (P < 0.01). Across land uses, annual CO2 fluxes were positively correlated with soil organic carbon (C) and negatively correlated with 15N signatures, extractable P and base saturation. This suggests that the reduced soil CO2 fluxes from oil palm was a result of strongly decomposed soil organic matter due to reduced litter input, and possible reduction in C allocation to roots due to improved soil fertility from liming and P fertilization in these plantations. Soil CH4 uptake in the reference land uses was negatively correlated with net nitrogen (N) mineralization and soil mineral N, suggesting N limitation of CH4 uptake, and positively correlated with exchangeable aluminum (Al), indicating decrease in methanotrophic activity at high Al saturation. Reduction in soil CH4 uptake in the converted land uses compared to the reference land uses (P < 0.01) was due to decrease in soil N availability in the converted

  16. Mid-infrared spectroscopy for rapid assessment of soil properties after land use change from pastures to Eucalyptus globulus plantations.

    PubMed

    Madhavan, Dinesh B; Kitching, Matt; Mendham, Daniel S; Weston, Christopher J; Baker, Thomas G

    2016-06-15

    There is an increasing demand for rapid and cost effective techniques to accurately measure the effects of land use change on soil properties. This study evaluated the ability of mid-infrared spectroscopy (MIRS) coupled with partial least squares regression (PLSR) to rapidly predict soil properties affected by land use change from agriculture (mainly pasture) to Eucalyptus globulus plantations in south-western Australia. We measured total organic carbon (TOC), total nitrogen (Total N), TOC/Total N (C/N ratio), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), and total phosphorus (Total P). The PLSR calibration models were developed using mid-infrared (MIR) spectra (4000 to 450 cm(-1)) and square root transformed measured soil data (n = 180) from 23 paired pasture and E. globulus plantation sites representing the soils and climate of E. globulus plantation estates in south-western Australia. The calibration models for TOC, Total N, C/N ratio and Total P showed excellent correlations between measured and predicted data with coefficient of determination (R(2)) exceeding 0.91 and minimum root-mean-square error (RMSE) of calibration [TOC (R(2) = 0.95, RMSE = 0.36), Total N (R(2) = 0.96, RMSE = 0.10), C/N ratio (R(2) = 0.92, RMSE = 0.14) and Total P (R(2) = 0.91, RMSE = 0.06)]. The calibration models had reasonable predictions for MBC (R(2) = 0.66, RMSE = 0.07) and MBN (R(2) = 0.63, RMSE = 0.06). The calibrated models were validated using soils from 8 independent paired pasture and E. globulus sites (n = 64). The validated predictions were excellent for TOC (R(2) = 0.92, RMSE = 0.40) and Total N (R(2) = 0.91, RMSE = 0.12), but less so for C/N ratio (R(2) = 0.80, RMSE = 0.35), MBC (R(2) = 0.70, RMSE = 0.08) and Total P (R(2) = 0.75, RMSE = 0.12). The results demonstrate the potential of MIRS-PLSR to rapidly, accurately and simultaneously determine several properties in land use change affected soils. PMID:27043775

  17. Soil Carbon Losses after Rainforest Conversion to Oil Palm and Rubber Plantations: Processes and Sensitivity of Soil Fertility Indicators Assessed by a New Approach

    NASA Astrophysics Data System (ADS)

    Guillaume, T.; Maranguit, D.; Murtilaksono, K.; Kuzyakov, Y.

    2015-12-01

    Tropical forest conversion to agricultural land leads to strong decrease of soil organic matter (SOM). Nonetheless, the magnitude of SOM losses and their impacts on soil fertility in oil palm and rubber plantations remain unclear, despite the large scale extension of such land-use types. We quantified SOM losses, and estimated soil erosion and changes in SOM turnover using SOM δ13C values in forest, oil palm plantations, extensive rubber plantations and rubber monocultures on Sumatra Island (Indonesia). Further, we assessed the response of biological (basal respiration, microbial biomass, acid phosphatase) and chemical fertility indicators (light fraction, DOC, total N, available P) to SOM losses. We used a new approach based on (non-)linear regressions between SOM losses and the indices standardized to natural ecosystem. Carbon contents in the Ah horizon under oil palm and rubber plantations were strongly reduced: up to 70% and 62%, respectively. The decrease was lower under extensive rubber (41%). The estimated erosion was the strongest in oil palm (35±8 cm) and rubber (33±10 cm) plantations. The SOM 13C enrichment used as a proxy of its turnover indicates a decrease of SOM turnover under oil palm after forest conversion. The negative impact of land-use changes on all measured indicators increased in the following sequence: forest > extensive rubber > rubber > oil palm. The basal respiration, microbial biomass and nutrients were comparatively resistant to SOM losses, whereas the light fraction was lost faster than the SOM. The resistance of the microbial activity to SOM losses is an indication that the microbial functions sustain SOM losses. However, responses of basal respiration and microbial biomass to SOM losses were non-linear. Below 2.7 % C content, the relationship was reversed. The basal respiration decreased faster than the SOM, resulting in a stronger drop of microbial activity under oil palm compared to rubber despite small difference in C content

  18. Functional Assays and Metagenomic Analyses Reveals Differences between the Microbial Communities Inhabiting the Soil Horizons of a Norway Spruce Plantation

    PubMed Central

    Uroz, Stéphane; Ioannidis, Panos; Lengelle, Juliette; Cébron, Aurélie; Morin, Emmanuelle; Buée, Marc; Martin, Francis

    2013-01-01

    In temperate ecosystems, acidic forest soils are among the most nutrient-poor terrestrial environments. In this context, the long-term differentiation of the forest soils into horizons may impact the assembly and the functions of the soil microbial communities. To gain a more comprehensive understanding of the ecology and functional potentials of these microbial communities, a suite of analyses including comparative metagenomics was applied on independent soil samples from a spruce plantation (Breuil-Chenue, France). The objectives were to assess whether the decreasing nutrient bioavailability and pH variations that naturally occurs between the organic and mineral horizons affects the soil microbial functional biodiversity. The 14 Gbp of pyrosequencing and Illumina sequences generated in this study revealed complex microbial communities dominated by bacteria. Detailed analyses showed that the organic soil horizon was significantly enriched in sequences related to Bacteria, Chordata, Arthropoda and Ascomycota. On the contrary the mineral horizon was significantly enriched in sequences related to Archaea. Our analyses also highlighted that the microbial communities inhabiting the two soil horizons differed significantly in their functional potentials according to functional assays and MG-RAST analyses, suggesting a functional specialisation of these microbial communities. Consistent with this specialisation, our shotgun metagenomic approach revealed a significant increase in the relative abundance of sequences related glycoside hydrolases in the organic horizon compared to the mineral horizon that was significantly enriched in glycoside transferases. This functional stratification according to the soil horizon was also confirmed by a significant correlation between the functional assays performed in this study and the functional metagenomic analyses. Together, our results suggest that the soil stratification and particularly the soil resource availability impact the

  19. Impacts of afforestation and silviculture on the soil C balance of tropical tree plantations: belowground C allocation, soil CO2 efflux and C accretion (Invited)

    NASA Astrophysics Data System (ADS)

    Epron, D.; Koutika, L.; Mareschal, L.; Nouvellon, Y.

    2013-12-01

    Tropical forest plantations will provide a large part of the global wood supply which is anticipated to increase sharply in the next decades, becoming a valuable source of income in many countries, where they also contribute to land use changes that impact the global carbon (C) cycle. Tropical forest plantations established on previous grasslands are potential C sinks offsetting anthropogenic CO2 emissions. When they are managed on short rotations, the aboveground biomass is frequently removed and transformed into wood products with short lifetimes. The soil is thus the only compartment for durable C sequestration. The soil C budget results from the inputs of C from litterfall, root turnover and residues left at logging stage, balanced by C losses through heterotrophic respiration and leaching of organic C with water flow. Intensive researches have been conducted these last ten years in eucalypt plantations in the Congo on the effects of management options on soil fertility improvement and C sequestration. Our aim is to review important results regarding belowground C allocation, soil CO2 efflux and C accretion in relation to management options. We will specifically address (i) the soil C dynamics after afforestation of a tropical savannah, (ii) the impact of post-harvest residue management, and (iii) the beneficial effect of introducing nitrogen fixing species for C sequestration. Our results on afforestation of previous savannah showed that mechanical soil disturbance for site preparation had no effect on soil CO2 efflux and soil C balance. Soil C increased after afforestation despite a rapid disappearance of the labile savannah-derived C because a large fraction of savannah-derived C is stable and the aboveground litter layer is as the major source of CO2 contributing to soil CO2 efflux. We further demonstrated that the C stock in and on the soil slightly increased after each rotation when large amounts of residues are left at logging stage and that most of

  20. Large difference of inhibitive effect of nitrogen deposition on soil methane oxidation between plantations with N-fixing tree species and non-N-fixing tree species

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Zhu, Xiaomin; Liu, Lei; Fu, Shenglei; Chen, Hao; Huang, Juan; Lu, Xiankai; Liu, Zhanfeng; Mo, Jiangming

    2012-12-01

    The responses of soil methane (CH4) net fluxes to nitrogen (N) addition in a N-fixing tree species (Acacia auriculiformis (AA)) and a non-N-fixing tree species (Eucalyptus citriodora (EU)) plantation were studied in southern China. Treatments were conducted at each plantation with three N levels (0, 50, and 100 kg N ha-1 yr-1 for control, medium-N, and high-N treatment, respectively, abbreviated as C, MN, and HN). From August 2010 to July 2011, CH4 flux was measured biweekly using a static chamber and gas chromatography technique. The soils of both sites acted as sink of atmospheric CH4. The CH4 uptake rate in control of the AA site (36.3 ± 3.2 μg CH4-C m-2 h-1) was greater than that of the EU plantation (29.9 ± 0.9 μg CH4-C m-2 h-1). In the AA plantation, the averaged rates of CH4 uptake for the MN (28.6 ± 2.3 μg CH4-C m-2 h-1) and HN treatment (23.8 ± 2.8 μg CH4-C m-2 h-1) were decreased by 21% and 35%, respectively, compared to the control. However, there was no change of soil CH4 uptake between N-treated plots and the controls in the EU site. Our results indicated that there might be large difference of inhibitive effect of N deposition on soil CH4 oxidation between the AA and EU plantations. The projected increase of N deposition would weaken the capability of N-fixing tree species plantations for atmospheric CH4 sink in tropical and subtropical regions.

  1. Soil carbon changes after plantation of autochthonous species in a semi-arid Mediterranean old-field in Sardinia

    NASA Astrophysics Data System (ADS)

    de Dato, Giovanbattista; de Angelis, Paolo

    2010-05-01

    Forested areas are important in arid and semi-arid regions primarily to combat desertification, but also to increase carbon sinks. According to the last Italian National Inventory of Forest and Carbon INFC dated 2005, Mediterranean maquis and shrublands cover about 690,100 ha, in Italy. Considering their vast diffusion, efforts should be done to evaluate the potential of these ecosystems in sequestering C in order to achieve the Kyoto Protocol commitments and dampen desertification processes. The aim of this work was to present preliminary observations on soil C accumulation and release in a planted Mediterranean semi-arid shrubland. During the first three years particular effort was done to quantify the plant growth and soil CO2 emission, to test if species-specific responses could be detectable and relevant for the C-budget. The experimental area is located in North West Sardinia, and is characterized by a Mediterranean climate. The revegetation was set up in February 2006, in an old-field, planting local species (Juniperus phoenicea, Pistacia lentiscus and Rosmarinus officinalis) in mono-specific or mixed plots. Soil total organic carbon and nitrogen was measured at the same time of plantation and after 3 years, collecting soil cores (144 samples) at two depths (0-20 cm and 20-40 cm). Moreover, in order to measure soil CO2 emissions, 4 collars are inserted into the soil at 30-60-90-120 cm from 3 plants per each species. Measurements have being made monthly since July 2006 by a portable IRGA. Presently, soil C in the studied area is about 0.7 - 0.8 t ha-1. Based on soil CO2 emissions measurements (≈7 t C ha-1 yr-1) and on the low biomass accumulation (0.25-0.60 t ha-1 yr-1), the plantation is at the present a net C source. This is an effect of the low plant growth, very little input from litter, and the contemporary mineralization of old C deriving from the preceding agricultural phase (priming effect).

  2. Characterization of Arbuscular Mycorrhizal Fungus Communities of Aquilaria crassna and Tectona grandis Roots and Soils in Thailand Plantations

    PubMed Central

    Chaiyasen, Amornrat; Young, J. Peter W.; Teaumroong, Neung; Gavinlertvatana, Paiboolya; Lumyong, Saisamorn

    2014-01-01

    Aquilaria crassna Pierre ex Lec. and Tectona grandis Linn.f. are sources of resin-suffused agarwood and teak timber, respectively. This study investigated arbuscular mycorrhizal (AM) fungus community structure in roots and rhizosphere soils of A. crassna and T. grandis from plantations in Thailand to understand whether AM fungal communities present in roots and rhizosphere soils vary with host plant species and study sites. Terminal restriction fragment length polymorphism complemented with clone libraries revealed that AM fungal community composition in A. crassna and T. grandis were similar. A total of 38 distinct terminal restriction fragments (TRFs) were found, 31 of which were shared between A. crassna and T. grandis. AM fungal communities in T. grandis samples from different sites were similar, as were those in A. crassna. The estimated average minimum numbers of AM fungal taxa per sample in roots and soils of T. grandis were at least 1.89 vs. 2.55, respectively, and those of A. crassna were 2.85 vs. 2.33 respectively. The TRFs were attributed to Claroideoglomeraceae, Diversisporaceae, Gigasporaceae and Glomeraceae. The Glomeraceae were found to be common in all study sites. Specific AM taxa in roots and soils of T. grandis and A. crassna were not affected by host plant species and sample source (root vs. soil) but affected by collecting site. Future inoculum production and utilization efforts can be directed toward the identified symbiotic associates of these valuable tree species to enhance reforestation efforts. PMID:25397675

  3. Assessment of 10 years of CO2 fumigation on soil microbial communities and function in a sweetgum plantation

    SciTech Connect

    Austin, Emily E; Castro Gonzalez, Hector F; Sides, Katherine E; Schadt, Christopher Warren; Classen, Aimee T

    2009-01-01

    Increased vegetative growth and soil carbon (C) storage under elevated carbon dioxide concentration ([CO2]) has been demonstrated in a number of experiments. However, the ability of ecosystems, either above- or belowground, to maintain increased carbon storage relies on the response of soil processes, such as nitrogen (N) availability, to climatic change. These soil processes are mediated by microbial communities whose activity and structure may also respond to increasing atmospheric [CO2]. We took advantage of a long-term (ca 10 year) CO2 enrichment experiment in a sweetgum plantation located in Tennessee to test the hypothesis that observed increases in root production in elevated relative to ambient CO2 plots would alter microbial community structure, increase microbial activity, and increase soil nutrient cycling. We found that elevated [CO2] had no detectable effect on microbial community structure using 16S rRNA gene cloning libraries, on microbial activity measured with extracellular enzyme activity, or on potential soil N mineralization and nitrification rates. These results are similar to those found at other sites and are consistent with continued C storage in forest ecosystems in the near future.

  4. Characterization of arbuscular mycorrhizal fungus communities of Aquilaria crassna and Tectona grandis roots and soils in Thailand plantations.

    PubMed

    Chaiyasen, Amornrat; Young, J Peter W; Teaumroong, Neung; Gavinlertvatana, Paiboolya; Lumyong, Saisamorn

    2014-01-01

    Aquilaria crassna Pierre ex Lec. and Tectona grandis Linn.f. are sources of resin-suffused agarwood and teak timber, respectively. This study investigated arbuscular mycorrhizal (AM) fungus community structure in roots and rhizosphere soils of A. crassna and T. grandis from plantations in Thailand to understand whether AM fungal communities present in roots and rhizosphere soils vary with host plant species and study sites. Terminal restriction fragment length polymorphism complemented with clone libraries revealed that AM fungal community composition in A. crassna and T. grandis were similar. A total of 38 distinct terminal restriction fragments (TRFs) were found, 31 of which were shared between A. crassna and T. grandis. AM fungal communities in T. grandis samples from different sites were similar, as were those in A. crassna. The estimated average minimum numbers of AM fungal taxa per sample in roots and soils of T. grandis were at least 1.89 vs. 2.55, respectively, and those of A. crassna were 2.85 vs. 2.33 respectively. The TRFs were attributed to Claroideoglomeraceae, Diversisporaceae, Gigasporaceae and Glomeraceae. The Glomeraceae were found to be common in all study sites. Specific AM taxa in roots and soils of T. grandis and A. crassna were not affected by host plant species and sample source (root vs. soil) but affected by collecting site. Future inoculum production and utilization efforts can be directed toward the identified symbiotic associates of these valuable tree species to enhance reforestation efforts. PMID:25397675

  5. Changes in the soil microbial community with a pine plantation restoration in a dry valley of the upper reaches of the Minjiang River, southwest China.

    PubMed

    Liu, Zhanfeng; Liu, Guohua; Fu, Bojie; Wu, Yaqiong; Hu, Huifeng; Fu, Shenglei

    2010-05-01

    The objective of this study was to investigate the changes in soil microbial biomass C, microbial metabolic activity, functional diversity, and metabolic diversity pattern during the restoration process of a pine (Pinus tabulaeformis) plantation. In this study, a chronosequence approach was adopted. Three sites of pine plantations along a restoration chronosequence (12 years old (PF12), 25 years old (PF25), 35 years old (PF35)), and their paired reference sites of natural shrub community (Shrub1, Shrub2, and Shrub3) were selected. Soil microbial biomass C increased and microbial quotient declined with pine plantation age. Microbial metabolic activity, as measured by average well color development (using Biolog GN(2) plates), exhibited a decline along the restoration chronosequence with values ranked as PF12 > PF35 > PF25 in topsoil and PF12 > PF25 > PF35 in subsoil. Functional diversity, as estimated by substrate diversity and substrate richness, exhibited a pattern similar to the metabolic activity. Principal component analysis indicated that metabolic diversity followed recognized patterns along the restoration chronosequence with PF12 significantly different from PF25 and PF35. There was an apparent reduction of microbial metabolic activity and functional diversity during pine plantation restoration, which can be explained by a general decline in soil nutrient availability, particularly C availability, and soil pH associated with the establishment of a coniferous species. PMID:20586776

  6. Soil carbon dioxide and methane fluxes from lowland forests converted to oil palm and rubber plantations in Sumatra, Indonesia

    NASA Astrophysics Data System (ADS)

    Preuss, Evelyn; Corre, Marife D.; Damris, Muhammad; Tjoa, Aiyen; Rahayu Utami, Sri; Veldkamp, Edzo

    2015-04-01

    Demand for palm oil has increased strongly in recent decades. Global palm oil production quadrupled between 1990 and 2009, and although almost half of the global supply is already produced in Indonesia, a doubling of current production is planned for the next ten years. This agricultural expansion is achieved by conversion of rainforest. Land-use conversion affects soil carbon dioxide (CO2) and methane (CH4) fluxes through changes in nutrient availability and soil properties which, in turn, influence plant productivity, microbial activity and gas diffusivity. Our study was aimed to assess changes in soil CO2 and CH4 fluxes with forest conversion to oil palm and rubber plantations. Our study area was Jambi Province, Sumatra, Indonesia. We selected two soil landscapes in this region: loam and clay Acrisol soils. At each landscape, we investigated four land-use systems: lowland secondary rainforest, secondary forest with regenerating rubber (referred here as jungle rubber), rubber (7-17 years old) and oil palm plantations (9-16 years old). Each land use in each soil landscape was represented by four sites as replicates, totaling to 32 sites. We measured soil-atmosphere CH4 and CO2 fluxes using vented static chamber method with monthly sampling from November 2012 to December 2013. There were no differences in soil CO2 and CH4 fluxes (all P > 0.05) between soil landscapes for each land-use type. For soil CO2 fluxes, in both clay and loam Acrisol soil landscapes oil palm were lower compared to the other land uses (P < 0.007). In the clay Acrisol, soil CO2 fluxes were 107.2 ± 7.2 mg C m-2 h-1 for oil palm, and 195.9 ± 13.5 mg C m-2 h-1for forest, 185.3 ± 9.4 mg C m-2 h-1for jungle rubber and 182.8 ± 16.2 mg C m2 h-1for rubber. In the loam Acrisol, soil CO2 fluxes were 115.7 ± 11.0 mg CO2-C m2 h-1 for oil palm, and 186.6 ± 13.7, 178.7 ± 11.2, 182.9 ± 14.5 mg CO2-C m-2 h-1 for forest, jungle rubber and rubber, respectively. The seasonal patterns of soil CO2 fluxes

  7. Soil properties in different types of Eucalypt Plantations in a small forested watershed, north-central Portugal

    NASA Astrophysics Data System (ADS)

    Santos, J. M.; van Beersum, S.; van Hall, I.; Bernard-Jannin, L.; Rial-Rivas, M. E.; Nunes, J. P.; Keizer, J. J.

    2012-04-01

    The main aim of the HIDRIA project is to improve the knowledge and understanding of factors and processes that determine the hydrological behaviour of forested foothills in the Caramulo mountain range, North-Central Portugal. The changes from natural forest cover to Eucalyptus plantations in the last decades in Portugal is present in Serra de Cima catchment, one of the four experimental catchments monitored within the framework of the project. The objectives of the present study are to determine the effects of these changes on soil properties, and to improve the parameterization of the SWAT model to simulate the impact of land-use changes associated with forestry practices on hydrological processes. The study catchment (Serra de Cima) is located in the Águeda Basin, draining the foothills of the Caramulo mountains east of Águeda (40°36'N, -8°20'E). The climate is wet Mediterranean with a mean annual precipitation of about 1600 mm at 445 m a.s.l. Soils are generally Umbric Leptosols (<30 cm depth) and Humic Cambisols. The Serra de Cima catchment has an area of 0.52 km2 and is covered by commercial eucalypt plantations (73% of the total area) and natural/degraded pine forest (27% of the total area). Eucalypts are managed as Short Rotation Coppices, with each stand growing during 30-36 years; trees are cut every 10-12 years and stems re-grow from roots afterwards. The eucalypt stands in the study area differ in tree age, undergoing their first, second or third rotations. Climate, soil moisture and streamflow are monitored at the catchment. The presentation will focus on the results of a field campaign done on June 2011 to characterize soil and vegetation properties for six points on eucalypt stands in different stages of growth, as well as pine stands. The parameters sampled in this campaign were selected based on a sensitivity analysis of the SWAT model, and included: tree density and diameter; Leaf Area Index (LAI); ground cover; profile description; dry bulk

  8. Soil carbon and nitrogen cycling and storage throughout the soil profile in a sweetgum plantation after 11 years of CO2-enrichment

    SciTech Connect

    Iversen, Colleen M; Keller, Dr. Jason K.; Garten Jr, Charles T; Norby, Richard J

    2012-01-01

    Increased partitioning of carbon (C) to fine roots under elevated [CO2], especially deep in the soil profile, could alter soil C and nitrogen (N) cycling in forests. After more than 11 years of free-Air CO2 enrichment in a Liquidambar styraciflua L. (sweetgum) plantation in Oak Ridge, TN, USA, greater inputs of fine roots resulted in the incorporation of new C (i.e., C with a depleted 13C) into root-derived particulate organic matter (POM) pools to 90-cm depth. Even though production in the sweetgum stand was limited by soil N availability, soil C and N content increased over time, and were greater throughout the soil profile under elevated [CO2] at the conclusion of the experiment. However, greater C inputs under elevated [CO2] did not result in increased net N immobilization or C mineralization rates in long-term laboratory incubations, and did not appear to prime the decomposition of older SOM. The 13CO2 of the C mineralized from the incubated soil closely tracked the 13C of the labile POM pool in the elevated [CO2] treatment, especially in shallower soil, and did not indicate the decomposition of older (i.e., pre-experiment) SOM. While potential C mineralization rates were positively and linearly related to total soil organic matter (SOM) C content in the top 30 cm of soil, this relationship did not hold in deeper soil. Taken together with an increased mean residence time of C in deeper soil pools, these findings indicate that C inputs from relatively deep roots under elevated [CO2] may have increased potential for long-term storage. Expanded representation of biogeochemical cycling throughout the soil profile may improve model projections of future forest responses to rising atmospheric [CO2].

  9. [Seasonal fluctuation of soil microbial biomass carbon in secondary oak forest and Pinus taeda plantation in north subtropical area of China].

    PubMed

    Wang, Guo-bing; Ruan, Hong-hua; Tang, Yan-fei; Luan, Yi-ling; Chen, Yue-qin; Tao, Zhong-fang

    2008-01-01

    With random block experimental design, the soil microbial biomass carbon, soil temperature, soil moisture, and litterfall input in secondary oak forest and Pinus taeda plantation were measured in successive two years at the Xiashu Experimental Forest of Nanjing Forestry University. The results showed that in the two stands, soil microbial biomass carbon had an obvious seasonal fluctuation, being lower in plant vigorous growth season but higher during plant dormancy. The microbial biomass carbon in 0-10 cm soil layer ranged from 267.8 mg x kg(-1) to 459.8 mg x kg(-1) in P. taeda plantation and from 278.6 mg x kg(-1) to 467.8 mg x kg(-1) in secondary oak forest. Soil microbial biomass carbon had a significant negative correlation with soil temperature, but no significant correlations with soil moisture and litterfall input. It was suggested that the seasonal fluctuation of soil microbial biomass carbon in test stands could be more related to the availability of soil carbon and other nutrients, competition of plant roots for soil nutrients, and plant growth rhythm. PMID:18419069

  10. Economic wealth and soil erosion in new Citrus plantations in Eastern Spain or how to explain the Land Degradation

    NASA Astrophysics Data System (ADS)

    Giménez-Morera, Antonio; Cerdà, Artemio; Pereira, Pauloq

    2014-05-01

    We use to accept the idea that the best oranges are coming from Valecia Region in Eastern Spain. Although the oranges are originally from Eastern Asia, Valencia is having a mild climate in winter, with a low recurrency of frost and is strategically located close to the largest market of citrus: Western Europe. This resulted in a continuous growth of production and trade of citrus, and contributed to make the Valencia Region the largest World exporter (Bono, 2010). This economical success reached the highest point after the EU and Spain agreement in 1986. This expansion of citrus plantations were done on steep slopes allowed by the drip irrigation systems that does not need leveling the land as it was done by new farmers with large properties. The traditional farming of oranges was done in small properties, flood irrigation and leveled land. Those changes are triggering intense soil erosion rates such were shown by previous researchers in Valencia (Cerdà et al., 2009). This impact is also shown in other regions with a similar citrus production evolution, and China is a clear example (Wang et al., 2010; Liu et al., 2012). Land This research evaluate the relations between the investment (economic wealth) of the owners of citrus plantations and the soil erosion rates on their orchards. The economic wealth of the onwers was measured on the size of their properties and after an interview. The soil erosion rates were measured by means of rainfall simulation experiments in each farm by means of thunderstorms of 10 years return period (55 mm h-1). The results show that the soil losses in the new plantations are extremely high (> 10 Mg ha-1 y-1), and that we can show three types of orchards: < 0.99 ha; 1-10 ha and > 10.1. The soil erosion rates where positively related to the size of the farms. The higher erosion rates are shown also by the scientific literature review. Chemically treated plantations (Cerdà, 2002) show high erosion rates due to the road construction too

  11. Lignocellulose biomass production potential from poplar short rotation plantations on marginal land in Germany and their impact on soil organic carbon stocks

    NASA Astrophysics Data System (ADS)

    Haas, Edwin; Klatt, Steffen; Kiese, Ralf; Werner, Christian; Butterbach-Bahl, Klaus

    2013-04-01

    In this study we assess the potential of lignocellulose biomass production by short rotation plantations in Germany. To avoid conflicts with agricultural food production only marginal agricultural land was accounted, which is usually of low quality and productivity. The process-oriented biogeochemical model LandscapeDNDC was used in conjunction with the forest-growth model PSIM to simulate the yield of poplar grown in short-rotation plantations throw-out Germany. The model was validated on five sites with different climatic conditions in Central Europe. The study aims to assess the effects of biomass short rotation plantations on the soil organic carbon stocks in Germany by comparing the cultivation of the bioenergy crops against the former arable land use (taken from the NitroEurope database). Using regional model input, with climatic drivers and soil properties being the most important, the biomass production potential of poplar plantations was simulated. To limit short-term climatic effects on the simulation outcome, we simulated biomass yields from short-rotation (6 year) Populus plantations for three time slices (1990-1995, 2000-2005, and 2010-2015) with climate data taken from the NitroEurope database and provided the simulated yield averages and standard deviations of these runs as well as the changes in soil organic carbon stocks compared to the former land use due to the land use change. Considering 10% of the arable land with the lowest productivity, the model results in a biomass production of approximately 6.78 t DM / ha / year which is approx. 10.1 kilo t DM / year while the 10% of the arable land with the highest productivity result in 8.11 t DM / ha / year which is approx. 12.6 kilo t DM / year (averages over 3 simulation time slices). We will present results of transient simulations of several rotations with various rotation lengths for biomass yields and changes in soil organic carbon stocks.

  12. Soil fertility controls soil-atmosphere carbon dioxide and methane fluxes in a tropical landscape converted from lowland forest to rubber and oil palm plantations

    NASA Astrophysics Data System (ADS)

    Hassler, E.; Corre, M. D.; Tjoa, A.; Damris, M.; Utami, S. R.; Veldkamp, E.

    2015-10-01

    Expansion of palm oil and rubber production, for which global demand is increasing, causes rapid deforestation in Sumatra, Indonesia, and is expected to continue in the next decades. Our study aimed to (1) quantify changes in soil CO2 and CH4 fluxes with land-use change and (2) determine their controlling factors. In Jambi Province, Sumatra, we selected two landscapes on heavily weathered soils that differ mainly in texture: loam and clay Acrisol soils. In each landscape, we investigated the reference land-use types (forest and secondary forest with regenerating rubber) and the converted land-use types (rubber, 7-17 years old, and oil palm plantations, 9-16 years old). We measured soil CO2 and CH4 fluxes monthly from December 2012 to December 2013. Annual soil CO2 fluxes from the reference land-use types were correlated with soil fertility: low extractable phosphorus (P) coincided with high annual CO2 fluxes from the loam Acrisol soil that had lower fertility than the clay Acrisol soil (P < 0.05). Soil CO2 fluxes from the oil palm (107.2 to 115.7 mg C m-2 h-1) decreased compared to the other land-use types (between 178.7 and 195.9 mg C m-2 h-1; P < 0.01). Across land-use types, annual CO2 fluxes were positively correlated with soil organic carbon (C) and negatively correlated with 15N signatures, extractable P and base saturation. This suggests that the reduced soil CO2 fluxes from oil palm were the result of strongly decomposed soil organic matter and reduced soil C stocks due to reduced litter input as well as being due to a possible reduction in C allocation to roots due to improved soil fertility from liming and P fertilization in these plantations. Soil CH4 uptake in the reference land-use types was negatively correlated with net nitrogen (N) mineralization and soil mineral N, suggesting N limitation of CH4 uptake, and positively correlated with exchangeable aluminum (Al), indicating a decrease in methanotrophic activity at high Al saturation. Reduction in

  13. Spatial Heterogeneity of Soil Nutrients after the Establishment of Caragana intermedia Plantation on Sand Dunes in Alpine Sandy Land of the Tibet Plateau

    PubMed Central

    Li, Qingxue; Jia, Zhiqing; Zhu, Yajuan; Wang, Yongsheng; Li, Hong; Yang, Defu; Zhao, Xuebin

    2015-01-01

    The Gonghe Basin region of the Tibet Plateau is severely affected by desertification. Compared with other desertified land, the main features of this region is windy, cold and short growing season, resulting in relatively difficult for vegetation restoration. In this harsh environment, identification the spatial distribution of soil nutrients and analysis its impact factors after vegetation establishment will be helpful for understanding the ecological relationship between soil and environment. Therefore, in this study, the 12-year-old C. intermedia plantation on sand dunes was selected as the experimental site. Soil samples were collected under and between shrubs on the windward slopes, dune tops and leeward slopes with different soil depth. Then analyzed soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP) and available potassium (AK). The results showed that the spatial heterogeneity of soil nutrients was existed in C. intermedia plantation on sand dunes. (1) Depth was the most important impact factor, soil nutrients were decreased with greater soil depth. One of the possible reasons is that windblown fine materials and litters were accumulated on surface soil, when they were decomposed, more nutrients were aggregated on surface soil. (2) Topography also affected the distribution of soil nutrients, more soil nutrients distributed on windward slopes. The herbaceous coverage were higher and C. intermedia ground diameter were larger on windward slopes, both of them probably related to the high soil nutrients level for windward slopes. (3) Soil “fertile islands” were formed, and the “fertile islands” were more marked on lower soil nutrients level topography positions, while it decreased towards higher soil nutrients level topography positions. The enrichment ratio (E) for TN and AN were higher than other nutrients, most likely because C. intermedia is a leguminous

  14. Spatial Heterogeneity of Soil Nutrients after the Establishment of Caragana intermedia Plantation on Sand Dunes in Alpine Sandy Land of the Tibet Plateau.

    PubMed

    Li, Qingxue; Jia, Zhiqing; Zhu, Yajuan; Wang, Yongsheng; Li, Hong; Yang, Defu; Zhao, Xuebin

    2015-01-01

    The Gonghe Basin region of the Tibet Plateau is severely affected by desertification. Compared with other desertified land, the main features of this region is windy, cold and short growing season, resulting in relatively difficult for vegetation restoration. In this harsh environment, identification the spatial distribution of soil nutrients and analysis its impact factors after vegetation establishment will be helpful for understanding the ecological relationship between soil and environment. Therefore, in this study, the 12-year-old C. intermedia plantation on sand dunes was selected as the experimental site. Soil samples were collected under and between shrubs on the windward slopes, dune tops and leeward slopes with different soil depth. Then analyzed soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP) and available potassium (AK). The results showed that the spatial heterogeneity of soil nutrients was existed in C. intermedia plantation on sand dunes. (1) Depth was the most important impact factor, soil nutrients were decreased with greater soil depth. One of the possible reasons is that windblown fine materials and litters were accumulated on surface soil, when they were decomposed, more nutrients were aggregated on surface soil. (2) Topography also affected the distribution of soil nutrients, more soil nutrients distributed on windward slopes. The herbaceous coverage were higher and C. intermedia ground diameter were larger on windward slopes, both of them probably related to the high soil nutrients level for windward slopes. (3) Soil "fertile islands" were formed, and the "fertile islands" were more marked on lower soil nutrients level topography positions, while it decreased towards higher soil nutrients level topography positions. The enrichment ratio (E) for TN and AN were higher than other nutrients, most likely because C. intermedia is a leguminous shrub. PMID

  15. Temporal dynamics of runoff and soil loss on a plot scale under a coffee plantation on steep soil (Ultisol), Costa Rica

    NASA Astrophysics Data System (ADS)

    Villatoro-Sánchez, Mario; Le Bissonnais, Yves; Moussa, Roger; Rapidel, Bruno

    2015-04-01

    Soil erosion is a serious threat for cultivated soils on steep slopes under tropical conditions. In Costa Rica, coffee plantations are widespread on such steep slopes in several basins used for hydroelectric generation, which are affected by soil erosion and sedimentation in dam reservoirs. For this study, surface runoff and soil loss rate were measured during three years on large experimental plots installed within a coffee field on a steep slope (60% average). The time interval for rainfall and runoff measurements was 5 min. A simple infiltration model presented by Diskin and Nazimov (1995) was used to estimate runoff during a rainfall event showing the relevance of initial soil water content in order to estimate runoff base on rainfall intensity variations. Three complementary embedded time scales were analyzed: annual-monthly, event and intra-event. The rainy seasons included 581 rainfall events giving a total depth of 2206, 1778 and 2220 mm in 2011, 2012 and 2013 respectively. Total runoff was 103 ± 55, 54 ± 14 and 33 ± 6.4 mm in 2011, 2012 and 2013 respectively. Annual average sediment concentration was about 1.3 ± 0.3 g l-1 with reduced temporal variations between years or rainfall events. The total soil loss was 1686 ± 784, 914 ± 306 and 575 ± 140 kg ha-1 for 2011, 2012 and 2013 respectively. Around 60% of rainfall and 90% of runoff and soil loss respectively came from the August-October period and more than half of it from October. Total rainfall event and soil water content explained most of surface runoff and soil loss dynamics at three time scales analyzed. Inherited soil water storage from previous year played an important role on the relationship between rainfall and runoff dynamics the following year. Soil and coffee coverage did not have a significant effect on runoff and soil loss variability due to permanently good soil coverage (even in the rainy season). This good coverage over the rainy season prevented crust development. The presence of

  16. [Effects of understory removal and nitrogen addition on the soil chemical and biological properties of Pinus sylvestris var. mongolica plantation in Keerqin Sandy Land].

    PubMed

    Lin, Gui-Gang; Zhao, Qiong; Zhao, Lei; Li, Hui-Chao; Zeng, De-Hui

    2012-05-01

    A full factorial experiment was conducted to study the effects of understory removal and nitrogen addition (8 g x m(-2)) on the soil NO(3-)-N and NH(4+)-N concentrations, potential net nitrogen mineralization rate (PNM) and nitrification rate (PNN), microbial biomass C (MBC) and N (MBN), MBC/MBN, urease and acid phosphomonoesterase activities, and Olsen-P concentration in a Pinus sylvestris var. mongolica plantation in Keerqin Sandy Land during a growth season. Understory removal decreased the soil NH(4+)-N concentration, PNM, MBC, and MBN/MBN significantly, increased the soil Olsen-P concentration, but had little effects on the soil NO(3-)-N concentration, PNN, and urease and acid phosphomonoesterase activities. Nitrogen addition increased the soil NO(3-)-N concentration, PNM and PNN significantly, but had little effects on the other test properties. The interaction between understory removal and nitrogen addition had significant effects on the soil NH(4+)-N concentration, but little effects on the soil NO(3-)-N concentration. However, the soil NO(3-)-N concentration in the plots of understory removal with nitrogen addition was increased by 27%, compared with the plots of nitrogen addition alone, which might lead to the leaching of NO3-. It was suggested that understory vegetation could play an important role in affecting the soil chemical and biological properties in Mongolian pine plantations, and hence, the importance of understory vegetation should not be neglected when the forest management and restoration were implemented. PMID:22919826

  17. Impact of tapping and soil water status on fine root dynamics in a rubber tree plantation in Thailand

    PubMed Central

    Chairungsee, Naruenat; Gay, Frederic; Thaler, Philippe; Kasemsap, Poonpipope; Thanisawanyangkura, Sornprach; Chantuma, Arak; Jourdan, Christophe

    2013-01-01

    Fine roots (FR) play a major role in the water and nutrient uptake of plants and contribute significantly to the carbon and nutrient cycles of ecosystems through their annual production and turnover. FR growth dynamics were studied to understand the endogenous and exogenous factors driving these processes in a 14-year-old plantation of rubber trees located in eastern Thailand. FR dynamics were observed using field rhizotrons from October 2007 to October 2009. This period covered two complete dry seasons (November to March) and two complete rainy seasons (April to October), allowing us to study the effect of rainfall seasonality on FR dynamics. Rainfall and its distribution during the two successive years showed strong differences with 1500 and 950 mm in 2008 and 2009, respectively. FR production (FRP) completely stopped during the dry seasons and resumed quickly after the first rains. During the rainy seasons, FRP and the daily root elongation rate (RER) were highly variable and exhibited strong annual variations with a total FRP of 139.8 and 40.4 mm-2 and an average RER of 0.16 and 0.12 cm day-1 in 2008 and 2009, respectively. The significant positive correlations found between FRP, RER, the appearance of new roots, and rainfall at monthly intervals revealed the impact of rainfall seasonality on FR dynamics. However, the rainfall patterns failed to explain the weekly variations of FR dynamics observed particularly during the rainy seasons. At this time step, FRP, RER, and the appearance of new FR were negatively correlated to the average soil matric potential measured at a depth of between 30 and 60 cm. In addition, our study revealed a significant negative correlation between FR dynamics and the monthly production of dry rubber. Consequently, latex harvesting might disturb carbon dynamics in the whole tree, far beyond the trunk where the tapping was performed. These results exhibit the impact of climatic conditions and tapping system in the carbon budget of

  18. Impact of tapping and soil water status on fine root dynamics in a rubber tree plantation in Thailand.

    PubMed

    Chairungsee, Naruenat; Gay, Frederic; Thaler, Philippe; Kasemsap, Poonpipope; Thanisawanyangkura, Sornprach; Chantuma, Arak; Jourdan, Christophe

    2013-01-01

    Fine roots (FR) play a major role in the water and nutrient uptake of plants and contribute significantly to the carbon and nutrient cycles of ecosystems through their annual production and turnover. FR growth dynamics were studied to understand the endogenous and exogenous factors driving these processes in a 14-year-old plantation of rubber trees located in eastern Thailand. FR dynamics were observed using field rhizotrons from October 2007 to October 2009. This period covered two complete dry seasons (November to March) and two complete rainy seasons (April to October), allowing us to study the effect of rainfall seasonality on FR dynamics. Rainfall and its distribution during the two successive years showed strong differences with 1500 and 950 mm in 2008 and 2009, respectively. FR production (FRP) completely stopped during the dry seasons and resumed quickly after the first rains. During the rainy seasons, FRP and the daily root elongation rate (RER) were highly variable and exhibited strong annual variations with a total FRP of 139.8 and 40.4 mm(-) (2) and an average RER of 0.16 and 0.12 cm day(-) (1) in 2008 and 2009, respectively. The significant positive correlations found between FRP, RER, the appearance of new roots, and rainfall at monthly intervals revealed the impact of rainfall seasonality on FR dynamics. However, the rainfall patterns failed to explain the weekly variations of FR dynamics observed particularly during the rainy seasons. At this time step, FRP, RER, and the appearance of new FR were negatively correlated to the average soil matric potential measured at a depth of between 30 and 60 cm. In addition, our study revealed a significant negative correlation between FR dynamics and the monthly production of dry rubber. Consequently, latex harvesting might disturb carbon dynamics in the whole tree, far beyond the trunk where the tapping was performed. These results exhibit the impact of climatic conditions and tapping system in the carbon

  19. Humic Acid Composition and Characteristics of Soil Organic Matter in Relation to the Elevation Gradient of Moso Bamboo Plantations.

    PubMed

    Wang, Hsueh-Ching; Chou, Chiao-Ying; Chiou, Chyi-Rong; Tian, Guanglong; Chiu, Chih-Yu

    2016-01-01

    Studying the influence of climatic and/or site-specific factors on soil organic matter (SOM) along an elevation gradient is important for understanding the response of SOM to global warming. We evaluated the composition of SOM and structure of humic acids along an altitudinal gradient from 600 to 1400 m in moso bamboo (Phyllostachys edulis) plantations in central Taiwan using NMR spectroscopy and photometric analysis. Total organic C and total nitrogen (N) content increased with increasing elevation. Aromaticity decreased and ΔlogK (the logarithm of the absorbance ratio of humic acids at 400 and 600 nm) increased with increasing elevation, which suggests that SOM humification decreased with increasing elevation. High temperature at low elevations seemed to enhance the decomposition (less accumulation of total organic C and N) and humification (high aromaticity and low ΔlogK). The alkyl-C/O-alkyl-C (A/O-A) ratio of humic acids increased with increasing elevation, which suggests that SOM humification increased with increasing elevation; this finding was contrary to the trend observed for ΔlogK and aromaticity. Such a discrepancy might be due to the relatively greater remaining of SOM derived from high alkyl-C broadleaf litter of previous forest at high elevations. The ratio of recalcitrant C to total organic C was low at low elevations, possibly because of enhanced decomposition of recalcitrant SOM from the previous broadleaf forest during long-term intensive cultivation and high temperature. Overall, the change in SOM pools and in the rate of humification with elevation was primarily affected by changes in climatic conditions along the elevation gradient in these bamboo plantations. However, when the composition of SOM, as assessed by NMR spectroscopy and photometric analysis was considered, site-specific factors such as residual SOM from previous forest and intensive cultivation history could also have an important effect on the humic acid composition and

  20. Radiocarbon measurements of soil organic matter (SOM) and soil CO2 efflux provide unique insights into the SOM dynamics of managed loblolly pine plantations

    NASA Astrophysics Data System (ADS)

    Vogel, J. G.; Schuur, E. A.; Bracho, R.; Jokela, E. J.

    2011-12-01

    Soil organic matter (SOM) cycling between soils and the atmosphere affects a wide range of important ecosystem functions. However the key processes controlling this cycle, fine root inputs and heterotrophic respiration, are poorly understood primarily because they are difficult to directly measure in the field. Radiocarbon measurements and simple models can be used to evaluate the relative influence of these processes on SOM cycling. Here we used radiocarbon measurements of density separated SOM, and root respiration, microbial respiration, and soil CO2 efflux to examine the relative effect of two forestry practices, fertilization and the genetic control of planted seedlings, on SOM cycling in two loblolly pine plantation forests in north central Florida. Our primary hypothesis was that greater aboveground growth would correspond to increased inputs of C to the soil as root biomass, and a greater efflux of CO2 from roots and soil microbes. For the density separated fractions, the light fraction (LF) (<1.6 g cm-3) was nearly 98% of the SOM in these sandy soils, and the LF decreased significantly (p<0.05) with increasing levels of fertilization for the A horizon (~0-30 cm). Light fraction radiocarbon values ranged from 66-127% and tended to be more enriched in bomb carbon, or older, with increasing levels of fertilization. Based on a significant reduction in fine root biomass with fertilization, we estimate that the smaller mass of the LF and its older age were the result of less fine root contributions of C to the LF pool. The alternative hypothesis, that fertilization increased SOM turnover, was not supported. To determine if changes in root biomass reflected changes in root respiration in soil CO2 efflux, we estimated radiocarbon values for root and microbial respiration, and soil CO2 efflux in order to partition the components in soil CO2 efflux. Radiocarbon estimates of microbial respiration (0-15 cm depth) and root respiration fractions ranged from 55-67% and

  1. Soil carbon stock and total nitrogen in Hawaiian sugarcane commercial plantations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There has been a recent, renewed interest in Hawaiian sugarcane as a biofuel feedstock. However, there is little information on how much soil carbon (C) and nitrogen (N) is stored in Hawaiian sugarcane fields under normal, monoculture operations. Soil C and N data are needed to assess the life cycl...

  2. The use of chipped pruned branches to control the soil and water losses in citrus plantations in Eastern Spain

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; Keesstra, Saskia; Jordán, Antonio; Pereira, Paulo; Prosdocimi, Massimo; Ritsema, Coen J.; Burguet, María

    2016-04-01

    three sites the soil erosion is reduced in one order of magnitude in average as a consequence of the cover of the chipped pruned branches (78.45 % in average cover) in comparison to the bare (control) soils. Acknowledgements The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603498 (RECARE project). References Berendse, F., van Ruijven, J., Jongejans, E., Keesstra, S. 2015. Loss of plant species diversity reduces soil erosion resistance. Ecosystems, 18 (5), 881-888. DOI: 10.1007/s10021-015-9869-6 Biswas H., Raizada A., Mandal D., Kumar S., Srinivas S., Mishra P. K. 2015. Identification of areas vulnerable to soil erosion risk in India using GIS methods. Solid Earth, 6 (4), pp. 1247-1257. DOI: 10. 5194/se-6-1247-2015v Brevik, E. C., Cerdà, A., Mataix-Solera, J., Pereg, L., Quinton, J. N., Six, J., and Van Oost, K.: The interdisciplinary nature of SOIL, SOIL, 1, 117-129, doi:10.5194/soil-1-117-2015, 2015. Cerdà, A., Giménez-Morera, A. and Bodí, M.B. 2009.Soil and water losses from new citrus orchards growing on sloped soils in the western Mediterranean basin. Earth Surface Processes and Landforms, 34, 1822-1830. DOI: 10.1002/esp.1889 Cerdà, A., González-Pelayo, O., Giménez-Morera, A., Jordán, A., Pereira, P., Novara, A., Brevik, E.C., Prosdocimi, M., Mahmoodabadi, M., Keesstra, S., García Orenes, F., Ritsema, C., 2015. The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency - high magnitude simulated rainfall events. Soil Res. (In press) Colazo, J.C., Buschiazzo, D. 2015. The Impact of Agriculture on Soil Texture Due to Wind Erosion.Land Degradation and Development, 26 (1), 62-70 DOI: 10.1002/ldr.2297 Decock, C.,J. Lee, M. Necpalova, E. I. P. Pereira, D. M. Tendall, J. Six. 2015 Mitigating N2O emissions from soil: from patching leaks to transformative action. SOIL, 1, 687-694, doi:10

  3. Changes to Extractable Soil Amino Compounds Under Elevated CO2 and Ozone in an Aspen Plantation

    NASA Astrophysics Data System (ADS)

    Top, S. M.; Filley, T. R.; Zhang, X.

    2011-12-01

    Forests growing under elevated concentrations of atmospheric CO2 and ozone exhibit changes to root and foliar chemistry and quality that are related to changes in physiology, N limitation, and leaf damage. Additionally, there are documented changes to the activity of some understory invertebrate populations, and a variety of responses to soil organic matter ranging from accrual in the upper few centimeters to loss of soil C and N over the upper 20 cm. Under such conditions, however, the cycling of specific amino compounds is poorly understood. Knowledge of the role that new plant N plays in supporting soil microbial populations and soil C and N dynamics is important to fully understand relationships between N limitation under elevated CO2-induced productivity increases and available organic N pools in soil. We investigated the composition and concentration of hydrolysable amino compounds (amino acids and amino sugars) in litter, roots, soil, and earthworm fecal matter from the free-air CO2 enrichment (FACE) sites at Rhinelander, WI. Under elevated CO2 amino acids, when normalized to total N, exhibited change in both amount (decrease) and composition among roots (<2mm) with depth over the upper 25 cm, however, root amino acids showed only minor changes with depth in the ambient and ozone treatments. Ozonated rings exhibited a lower release of amino compounds (with respect to total N) compared to ambient and elevated CO2, which may suggest poorer quality input. For soil organic matter extractable amino acids (normalized to total soil N) exhibited changes similar to roots among the treatment. These results indicate that CO2 and ozone significantly influence amino compound dynamics in both soil and input which should impact the overall ability to decompose and preserve soils in such environments.

  4. The use of chipped pruned branches to control the soil and water losses in citrus plantations in Eastern Spain

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; Keesstra, Saskia; Jordán, Antonio; Pereira, Paulo; Prosdocimi, Massimo; Ritsema, Coen J.; Burguet, María

    2016-04-01

    three sites the soil erosion is reduced in one order of magnitude in average as a consequence of the cover of the chipped pruned branches (78.45 % in average cover) in comparison to the bare (control) soils. Acknowledgements The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603498 (RECARE project). References Berendse, F., van Ruijven, J., Jongejans, E., Keesstra, S. 2015. Loss of plant species diversity reduces soil erosion resistance. Ecosystems, 18 (5), 881-888. DOI: 10.1007/s10021-015-9869-6 Biswas H., Raizada A., Mandal D., Kumar S., Srinivas S., Mishra P. K. 2015. Identification of areas vulnerable to soil erosion risk in India using GIS methods. Solid Earth, 6 (4), pp. 1247-1257. DOI: 10. 5194/se-6-1247-2015v Brevik, E. C., Cerdà, A., Mataix-Solera, J., Pereg, L., Quinton, J. N., Six, J., and Van Oost, K.: The interdisciplinary nature of SOIL, SOIL, 1, 117-129, doi:10.5194/soil-1-117-2015, 2015. Cerdà, A., Giménez-Morera, A. and Bodí, M.B. 2009.Soil and water losses from new citrus orchards growing on sloped soils in the western Mediterranean basin. Earth Surface Processes and Landforms, 34, 1822-1830. DOI: 10.1002/esp.1889 Cerdà, A., González-Pelayo, O., Giménez-Morera, A., Jordán, A., Pereira, P., Novara, A., Brevik, E.C., Prosdocimi, M., Mahmoodabadi, M., Keesstra, S., García Orenes, F., Ritsema, C., 2015. The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency - high magnitude simulated rainfall events. Soil Res. (In press) Colazo, J.C., Buschiazzo, D. 2015. The Impact of Agriculture on Soil Texture Due to Wind Erosion.Land Degradation and Development, 26 (1), 62-70 DOI: 10.1002/ldr.2297 Decock, C.,J. Lee, M. Necpalova, E. I. P. Pereira, D. M. Tendall, J. Six. 2015 Mitigating N2O emissions from soil: from patching leaks to transformative action. SOIL, 1, 687-694, doi:10

  5. Temperature response of soil respiration in a Chinese pine plantation: hysteresis and seasonal vs. diel Q10.

    PubMed

    Jia, Xin; Zha, Tianshan; Wu, Bin; Zhang, Yuqing; Chen, Wenjing; Wang, Xiaoping; Yu, Haiqun; He, Guimei

    2013-01-01

    Although the temperature response of soil respiration (Rs ) has been studied extensively, several issues remain unresolved, including hysteresis in the Rs -temperature relationship and differences in the long- vs. short-term Rs sensitivity to temperature. Progress on these issues will contribute to reduced uncertainties in carbon cycle modeling. We monitored soil CO2 efflux with an automated chamber system in a Pinus tabulaeformis plantation near Beijing throughout 2011. Soil temperature at 10-cm depth (Ts ) exerted a strong control over Rs , with the annual temperature sensitivity (Q10) and basal rate at 10°C (Rs10) being 2.76 and 1.40 µmol m(-2) s(-1), respectively. Both Rs and short-term (i.e., daily) estimates of Rs10 showed pronounced seasonal hysteresis with respect to Ts , with the efflux in the second half of the year being larger than that early in the season for a given temperature. The hysteresis may be associated with the confounding effects of microbial population dynamics and/or litter input. As a result, all of the applied regression models failed to yield unbiased estimates of Rs over the entire annual cycle. Lags between Rs and Ts were observed at the diel scale in the early and late growing season, but not in summer. The seasonality in these lags may be due to the use of a single Ts measurement depth, which failed to represent seasonal changes in the depth of CO2 production. Daily estimates of Q10 averaged 2.04, smaller than the value obtained from the seasonal relationship. In addition, daily Q10 decreased with increasing Ts , which may contribute feedback to the climate system under global warming scenarios. The use of a fixed, universal Q10 is considered adequate when modeling annual carbon budgets across large spatial extents. In contrast, a seasonally-varying, environmentally-controlled Q10 should be used when short-term accuracy is required. PMID:23469089

  6. Temperature Response of Soil Respiration in a Chinese Pine Plantation: Hysteresis and Seasonal vs. Diel Q10

    PubMed Central

    Jia, Xin; Zha, Tianshan; Wu, Bin; Zhang, Yuqing; Chen, Wenjing; Wang, Xiaoping; Yu, Haiqun; He, Guimei

    2013-01-01

    Although the temperature response of soil respiration (Rs) has been studied extensively, several issues remain unresolved, including hysteresis in the Rs–temperature relationship and differences in the long- vs. short-term Rs sensitivity to temperature. Progress on these issues will contribute to reduced uncertainties in carbon cycle modeling. We monitored soil CO2 efflux with an automated chamber system in a Pinus tabulaeformis plantation near Beijing throughout 2011. Soil temperature at 10-cm depth (Ts) exerted a strong control over Rs, with the annual temperature sensitivity (Q10) and basal rate at 10°C (Rs10) being 2.76 and 1.40 µmol m−2 s−1, respectively. Both Rs and short-term (i.e., daily) estimates of Rs10 showed pronounced seasonal hysteresis with respect to Ts, with the efflux in the second half of the year being larger than that early in the season for a given temperature. The hysteresis may be associated with the confounding effects of microbial population dynamics and/or litter input. As a result, all of the applied regression models failed to yield unbiased estimates of Rs over the entire annual cycle. Lags between Rs and Ts were observed at the diel scale in the early and late growing season, but not in summer. The seasonality in these lags may be due to the use of a single Ts measurement depth, which failed to represent seasonal changes in the depth of CO2 production. Daily estimates of Q10 averaged 2.04, smaller than the value obtained from the seasonal relationship. In addition, daily Q10 decreased with increasing Ts, which may contribute feedback to the climate system under global warming scenarios. The use of a fixed, universal Q10 is considered adequate when modeling annual carbon budgets across large spatial extents. In contrast, a seasonally-varying, environmentally-controlled Q10 should be used when short-term accuracy is required. PMID:23469089

  7. [Effect of afforestation modes on soil microbial community and nitrogen functional genes in Hippophae rhamnoides plantation].

    PubMed

    Yang, Dan; Yu, Xuan; Liu, Xu; Liu, Jin-liana; Zhang, Shun-xiang; Yu, Ze-qun

    2015-12-01

    The study aimed to assess the effect of different afforestation modes on microbial composition and nitrogen functional genes in soil. Soil samples from a pure Hippophae rhamnoides stand (SS) and three mixed stands, namely, H. rhamnoides and Pinus tabuliformis (SY), H. rhamnoides and Platycladus orientalis (SB), H. rhamnoides and Robinia pseucdoacacia (SC) were selected. The results showed that the total PLFA (TPLFA), bacterial PLFA, gram positive bacterial PLFA (G⁺PLFA) were significantly higher in soil samples from other three stands than those of the pure one. However, no significant difference was found for fungal PLFA among them. The abundance of nifH, amoA, nirK and narG genes were higher in SY and SC than in SS. The TPLFA, G⁺PLFA, gram negative bacterial PLFA (G⁻PLFA), and all of the detected gene abundance were significantly and positively correlated with soil pH, total organic carbon, total nitrogen, ammonium nitrogen and available potassium. Afforestation modes affected indirectly soil microbial composition and functional genes through soil properties. Mixing P. tabuliformis or P. orientalis with H. rhamnoides might be suitable afforestation modes, which might improve soil quality. PMID:27111999

  8. Rice (Oryza sativa L) plantation affects the stability of biochar in paddy soil

    NASA Astrophysics Data System (ADS)

    Wu, Mengxiong; Feng, Qibo; Sun, Xue; Wang, Hailong; Gielen, Gerty; Wu, Weixiang

    2015-05-01

    Conversion of rice straw into biochar for soil amendment appears to be a promising method to increase long-term carbon sequestration and reduce greenhouse gas (GHG) emissions. The stability of biochar in paddy soil, which is the major determining factor of carbon sequestration effect, depends mainly on soil properties and plant functions. However, the influence of plants on biochar stability in paddy soil remains unclear. In this study, bulk and surface characteristics of the biochars incubated without rice plants were compared with those incubated with rice plants using a suite of analytical techniques. Results showed that although rice plants had no significant influence on the bulk characteristics and decomposition rates of the biochar, the surface oxidation of biochar particles was enhanced by rice plants. Using 13C labeling we observed that rice plants could significantly increase carbon incorporation from biochar into soil microbial biomass. About 0.047% of the carbon in biochar was incorporated into the rice plants during the whole rice growing cycle. These results inferred that root exudates and transportation of biochar particles into rice plants might decrease the stability of biochar in paddy soil. Impact of plants should be considered when predicting carbon sequestration potential of biochar in soil systems.

  9. Rice (Oryza sativa L) plantation affects the stability of biochar in paddy soil.

    PubMed

    Wu, Mengxiong; Feng, Qibo; Sun, Xue; Wang, Hailong; Gielen, Gerty; Wu, Weixiang

    2015-01-01

    Conversion of rice straw into biochar for soil amendment appears to be a promising method to increase long-term carbon sequestration and reduce greenhouse gas (GHG) emissions. The stability of biochar in paddy soil, which is the major determining factor of carbon sequestration effect, depends mainly on soil properties and plant functions. However, the influence of plants on biochar stability in paddy soil remains unclear. In this study, bulk and surface characteristics of the biochars incubated without rice plants were compared with those incubated with rice plants using a suite of analytical techniques. Results showed that although rice plants had no significant influence on the bulk characteristics and decomposition rates of the biochar, the surface oxidation of biochar particles was enhanced by rice plants. Using (13)C labeling we observed that rice plants could significantly increase carbon incorporation from biochar into soil microbial biomass. About 0.047% of the carbon in biochar was incorporated into the rice plants during the whole rice growing cycle. These results inferred that root exudates and transportation of biochar particles into rice plants might decrease the stability of biochar in paddy soil. Impact of plants should be considered when predicting carbon sequestration potential of biochar in soil systems. PMID:25944542

  10. Rice (Oryza sativa L) plantation affects the stability of biochar in paddy soil

    PubMed Central

    Wu, Mengxiong; Feng, Qibo; Sun, Xue; Wang, Hailong; Gielen, Gerty; Wu, Weixiang

    2015-01-01

    Conversion of rice straw into biochar for soil amendment appears to be a promising method to increase long-term carbon sequestration and reduce greenhouse gas (GHG) emissions. The stability of biochar in paddy soil, which is the major determining factor of carbon sequestration effect, depends mainly on soil properties and plant functions. However, the influence of plants on biochar stability in paddy soil remains unclear. In this study, bulk and surface characteristics of the biochars incubated without rice plants were compared with those incubated with rice plants using a suite of analytical techniques. Results showed that although rice plants had no significant influence on the bulk characteristics and decomposition rates of the biochar, the surface oxidation of biochar particles was enhanced by rice plants. Using 13C labeling we observed that rice plants could significantly increase carbon incorporation from biochar into soil microbial biomass. About 0.047% of the carbon in biochar was incorporated into the rice plants during the whole rice growing cycle. These results inferred that root exudates and transportation of biochar particles into rice plants might decrease the stability of biochar in paddy soil. Impact of plants should be considered when predicting carbon sequestration potential of biochar in soil systems. PMID:25944542

  11. Reducing the infectivity and richness of ectomycorrhizal fungi in a calcareous Quercus ilex forest through soil preparations for truffle plantation establishment: A bioassay study.

    PubMed

    Garcia-Barreda, Sergi; Molina-Grau, Sara; Reyna, Santiago

    2015-11-01

    In the early years of a black truffle plantation, the field proliferation of the nursery-inoculated fungi can be hampered by native ectomycorrhizal fungi colonising the seedling roots. Reducing the soil ectomycorrhizal infectivity in the planting hole before introducing the inoculated seedling could be an effective strategy to reduce this problem. Three bioassays were conducted to evaluate the impact of several soil preparations on the ectomycorrhizal infectivity and richness of a Quercus ilex soil in a truffle-producing region. Microwaves, quicklime, and acetic acid significantly decreased the percent root colonisation and morphotype richness of the native ectomycorrhizal fungi. However, they also decreased seedling survival or growth. Peracetic acid, hydrogen peroxide, and sodium hypochlorite did not show a significant negative effect on the soil ectomycorrhizal community. The results support the potential of soil preparation for reducing the ectomycorrhizal infectivity of forest soils, thus being a promising strategy to reduce the early colonisation by native fungi in truffle plantations. However, the indications of damage to the seedling development must be addressed. PMID:26466886

  12. [Effects of Different Plantation Type on the Abundance and Diversity of Soil Microbes in Subtropical Red Soils].

    PubMed

    Shen, Bing-jie; Zhu, Zhen-ke; Yuan, Hong-zhao; Ge, Ti-da; Wang, Jiu-rong; Chen, Ming-li; Wu, Xiao-fu; Wu, Jin-shui

    2015-10-01

    Soil microbe plays an important role in carbon cycling, however, the effect of land use on soil microbe remain unclear. In present study, soil samples were collected from a long-term field experiment (Pantang Agroecosystem) in subtropical China (established in 1989), including paddy-rice (PR), upland-crop (UC), and paddy rice-upland crop rotation (PU) on soil bacterial (bacteria and Archaea) community structures. The effects of long-term different land uses were determined using terminal restriction fragment length polymorphism (T-RFLP) and quantitative PCR (RT-PCR) of the 16S rRNA gene. The abundance of soil microbial 16S rRNA genes ranged from 2.5 x 10(9)-1.5 x 10(10) copies x g(-1) dry soil. Compared with the PR, UP and UC led to a significant reduction in 16S rRNA genes abundance (P < 0.05). The soil microbial communities were dominated by bacteria such as Proteobacteria (76 and 90 and 327 bp; relative abundance of 47% - 53%) and Chloroflexi (65 bp; relative abundance of 10% - 12%). RDA statistical analyses demonstrated that there were significant differences in the microbial community composition in PR, UC, and PU treated soils. Soil organic carbon and total nitrogen content were the most highly statistically significant factors which positively influenced the soil microbial population. Taken together, our findings prove the long-term different land uses significantly influence the microbial diversity and community structure. The rice planting is an effective way of sustainable utilization of subtropical red soil, and it is more advantageous to the accumulation of soil organic matter, soil fertility and microbial diversity. PMID:26841620

  13. Soil bacterial diversity in a loblolly pine plantation: influence of ectomycorrhizas and fertilization.

    PubMed

    Burke, David J; Kretzer, Annette M; Rygiewicz, Paul T; Topa, Mary A

    2006-09-01

    We studied the effect of ectomycorrhizas and fertilization on soil microbial communities associated with roots of 10-year-old loblolly pine. Ectomycorrhizas were identified using a combination of community terminal restriction fragment profiling and matching of individual terminal restriction fragments to those produced from ectomycorrhizal clones and sequences recovered from roots and sporocarps. Differences between bacterial communities were initially determined using cluster analysis on community terminal restriction fragment profiles and through subsequent recovery of 16S rDNA clones. Analysis of bacterial clones revealed that terminal restriction fragment length was often shared between taxonomically dissimilar bacterial types. Consequently, we could not reliably infer the identity of peaks in the bacterial community profile with some exceptions, notably chloroplast rDNA that generated an approximate peak size of 80.2 bp. Fertilization increased the frequency of a Piloderma-like ectomycorrhiza. However, we did not detect clear effects of fertilization or the presence of viable ectomycorrhizas on bacterial communities. Bacterial communities seemed to be determined largely by the carbon and nitrogen content of soil. These results suggest that important soil microbial groups respond differently to soil conditions and management practices, with ectomycorrhizal communities reflecting past nutrient conditions and bacterial communities reflecting current environmental conditions of soil microsites. PMID:16907755

  14. Heavy metal concentrations in redeveloping soil of mine spoil under plantations of certain native woody species in dry tropical environment, India.

    PubMed

    Singh, Anand N; Zeng, De-hui; Chen, Fu-sheng

    2005-01-01

    Total concentration of heavy metals (Cd, Cr, Cu, Fe, Pb, Ni, Mn and Zn) was estimated in the redeveloping soil of mine spoil under 5-yr old plantations of four woody species namely: Albizia lebbeck, Albizia procera, Tectona grandis and Dendrocalamus strictus. The data recorded in the present study were compared with other unplanted coal mine spoil colliery, which was around to the study site and adjoining area of dry tropical forest. Among all the heavy metals, the maximum concentration was found for Fe and minimum for Cd. However, among all four species, total concentrations of these heavy metals were recorded maximally in the plantation plots of T. grandis except for Fe, while minimally in A. lebbeck except for Zn, whereas, the maximum concentration of Fe and Zn was in the plantation plots of D. strictus and A. procera. Statistical analysis revealed significant differences due to species for all the heavy metals except Cu. Among four species, A. lebbeck, A. procera and D. strictus showed more efficient for reducing heavy metal concentrations whereas T. grandis was not more effective to reduce heavy metal concentrations in redeveloping soil of mine spoil. PMID:15900783

  15. [Changes in soil organic carbon and soil microbial functional diversity of Carya cathayensis plantations under intensive managements].

    PubMed

    Wu, Jia-Sen; Qian, Jin-Fang; Tong, Zhi-Peng; Huang, Jian-Qin; Zhao, Ke-Li

    2014-09-01

    The change characteristics of soil organic carbon and microbial function diversity in Chinese hickory Carya cathayensis stands with different intensive-management durations (5, 10, 15 and 20 years) were studied. The results showed that soil total organic carbon (TOC), microbial biomass carbon (MBC), water-soluble organic carbon (WSOC) decreased significantly, while the stability of soil C pool increased significantly after the conversion from evergreen and deciduous broadleaf forest to intensively-managed forest (IMF). TOC, MBC and WSOC in the hickory forest soil decreased by 28.4%, 34.1% and 53.3% with 5-year intensive management, and by 38.6%, 48.9% and 64.1% with 20-year intensive management, respectively. The proportions of carboxyl C, phenolic C and aromatic C in the hickory forest soil all increased significantly, and the aromaticity of soil organic C increased by 23.0%. Soil microbial functional diversity decreased greatly af- ter intensive management of Chinese hickory forest. Significant differences in average well color development (AWCD) were found between the 0- and 5-year treatments and the 10-, 15- and 20- year treatments. The microbial diversity indexes (H) and evenness indexes (E) in the 0- and 5-year treatments were much greater than in the 10- and 20-year treatments. Correlation analysis showed that there were significant correlations among soil TOC, WSOC, MBC, AWCD, H and E. PMID:25757296

  16. Changes in Biomass Carbon and Soil Organic Carbon Stocks following the Conversion from a Secondary Coniferous Forest to a Pine Plantation.

    PubMed

    Li, Shuaifeng; Su, Jianrong; Liu, Wande; Lang, Xuedong; Huang, Xiaobo; Jia, Chengxinzhuo; Zhang, Zhijun; Tong, Qing

    2015-01-01

    The objectives of this study were to estimate changes of tree carbon (C) and soil organic carbon (SOC) stock following a conversion in land use, an issue that has been only insufficiently addressed. For this study, we examined a chronosequence of 2 to 54-year-old Pinus kesiya var. langbianensis plantations that replaced the original secondary coniferous forest (SCF) in Southwest China due to clearing. C stocks considered here consisted of tree, understory, litter, and SOC (0-1 m). The results showed that tree C stocks ranged from 0.02±0.001 Mg C ha-1 to 141.43±5.29 Mg C ha-1, and increased gradually with the stand age. Accumulation of tree C stocks occurred in 20 years after reforestaion and C stock level recoverd to SCF. The maximum of understory C stock was found in a 5-year-old stand (6.74±0.7 Mg C ha-1) with 5.8 times that of SCF, thereafter, understory C stock decreased with the growth of plantation. Litter C stock had no difference excluding effects of prescribed burning. Tree C stock exhibited a significant decline in the 2, 5-year-old stand following the conversion to plantation, but later, increased until a steady state-level in the 20, 26-year-old stand. The SOC stocks ranged from 81.08±10.13 Mg C ha-1 to 160.38±17.96 Mg C ha-1. Reforestation significantly decreased SOC stocks of plantation in the 2-year-old stand which lost 42.29 Mg C ha-1 in the 1 m soil depth compared with SCF by reason of soil disturbance from sites preparation, but then subsequently recovered to SCF level. SOC stocks of SCF had no significant difference with other plantation. The surface profile (0-0.1 m) contained s higher SOC stocks than deeper soil depth. C stock associated with tree biomass represented a higher proportion than SOC stocks as stand development proceeded. PMID:26397366

  17. Changes in Biomass Carbon and Soil Organic Carbon Stocks following the Conversion from a Secondary Coniferous Forest to a Pine Plantation

    PubMed Central

    Li, Shuaifeng; Su, Jianrong; Liu, Wande; Lang, Xuedong; Huang, Xiaobo; Jia, Chengxinzhuo; Zhang, Zhijun; Tong, Qing

    2015-01-01

    The objectives of this study were to estimate changes of tree carbon (C) and soil organic carbon (SOC) stock following a conversion in land use, an issue that has been only insufficiently addressed. For this study, we examined a chronosequence of 2 to 54-year-old Pinus kesiya var. langbianensis plantations that replaced the original secondary coniferous forest (SCF) in Southwest China due to clearing. C stocks considered here consisted of tree, understory, litter, and SOC (0–1 m). The results showed that tree C stocks ranged from 0.02±0.001 Mg C ha-1 to 141.43±5.29 Mg C ha-1, and increased gradually with the stand age. Accumulation of tree C stocks occurred in 20 years after reforestaion and C stock level recoverd to SCF. The maximum of understory C stock was found in a 5-year-old stand (6.74±0.7 Mg C ha-1) with 5.8 times that of SCF, thereafter, understory C stock decreased with the growth of plantation. Litter C stock had no difference excluding effects of prescribed burning. Tree C stock exhibited a significant decline in the 2, 5-year-old stand following the conversion to plantation, but later, increased until a steady state-level in the 20, 26-year-old stand. The SOC stocks ranged from 81.08±10.13 Mg C ha-1 to 160.38±17.96 Mg C ha-1. Reforestation significantly decreased SOC stocks of plantation in the 2-year-old stand which lost 42.29 Mg C ha-1 in the 1 m soil depth compared with SCF by reason of soil disturbance from sites preparation, but then subsequently recovered to SCF level. SOC stocks of SCF had no significant difference with other plantation. The surface profile (0–0.1 m) contained s higher SOC stocks than deeper soil depth. C stock associated with tree biomass represented a higher proportion than SOC stocks as stand development proceeded. PMID:26397366

  18. Soil CO2, N2O and Nox Flux Responses to Biofuel Crop Plantation

    NASA Astrophysics Data System (ADS)

    Liang, L.; Eberwein, J.; Allsman, L.; Grantz, D. A.; Jenerette, D.

    2014-12-01

    Biofuel crops in high temperature environments, e.g, sorghum in southern California, USA, have a high capacity to assimilate atmospheric CO2. Photosynthates from the canopy may provide extra labile carbon source to feed soil microorganisms and influence trace gas fluxes, including CO2, N2O and NOx. Understanding how soil microorganisms balance the carbon (energy) and nitrogen (nutrients) allocation between growing microbial biomass and respiration is critical for evaluating the GHG emissions and emissions of regional air quality pollutants. We conducted experiments in a high temperature agroecosystem both in fallow and sorghum production fields with an experimental nitrogen gradient (0,50 and 100 kg/ha, marked as control, low and high with triplicate repeat) to investigate the CO2, N2O and NOx flux responses. All gas fluxes were measured simultaneously from three replicate locations for each treatment in the field biweekly. Measurements were performed 2-5 days after irrigation. We found that planting sorghum has significant effects on soil CO2 (p<0.0001), N2O (p<0.0001) and NOx (p=0.04) fluxes, but nitrogen amendments only have marginally significant effects on CO2 flux (p=0.07). Surprisingly, no significant response of N2O (p=0.27) and NOx (p=0.61) were observed in responses to N amendments. Compared to the fallow field, the CO2 flux in sorghum field increased 77%, 134% and 202% in control, low and high N level amendments, respectively. N2O flux from the sorghum field are consistently higher than from fallow field, with 207%, 174% and 1064% increase in control, low and high N level amendments, respectively. For the NOx flux, no significant difference was found between fallow and sorghum field. Although nitrogen amendments did not show significant effects on CO2, N2O and NOx flux, the high N treatment in sorghum field continuously gains the highest flux rates. Our results suggested additional C inputs may be an important factor regulating CO2, N2O and NOx fluxes in

  19. Effect of O horizon and Forest Harvest Residue Manipulations on Soil Organic Matter Content and Composition of a Loblolly Pine Plantation in the Southeastern United States

    NASA Astrophysics Data System (ADS)

    Hatten, J.; Mack, J.; Dewey, J.; Sucre, E.; Leggett, Z.

    2012-04-01

    Forest harvest residues and forest floor materials are significant sources of mineral soil organic matter and nutrients for regenerating and establishing forests. Harvest residues in particular are occasionally removed, piled, or burned following harvesting. While the forest floor is never purposely removed during operational harvesting and site preparation, they could become in high demand as bioenergy markets develop. Weyerhaeuser Company established an experimental study to evaluate the effect of forest-floor manipulation on site productivity and soil carbon. This study was installed in a loblolly pine plantation near Millport, Alabama, USA on the Upper Gulf Coastal Plain to test both extremes from complete removal of harvest residues and forest floor to doubling of these materials. This study has been continuously monitored since its establishment in 1994. We have examined the effects of varying forest floor levels on the biomass, soil carbon content, and soil carbon composition in the context of these management activities. Above- and below-ground productivity, soil moisture, soil temperature, and nutrient dynamics have been related to soil organic carbon in mineral soil size/density fractionation and lignin and cutin biomarkers from the cupric oxide (CuO) oxidation technique. We have found that while removing litter and harvest residues has little effect on biomass production and soil carbon, importing litter and harvest residues increases forest productivity and soil carbon content. Interestingly, increased carbon was observed in all depths assessed (O horizon, 0-20, 20-40, and 40-60cm) suggesting that this practice may sequester organic carbon in deep soil horizons. Our biomarker analysis indicated that importing litter and harvest residues increased relative contributions from above ground sources at the 20-40cm depth and increased relative contributions from belowground sources at the 40-60cm depth. These results suggest that organic matter manipulations

  20. Ecosystem-based greenhouse budgets in oil palm plantations differ with plantation age

    NASA Astrophysics Data System (ADS)

    Meijide, Ana; Hassler, Evelyn; Corre, Marife D.; June, Tania; Veldkamp, Edzo; Knohl, Alexander

    2016-04-01

    Global increase in demand of palm oil is leading to the expansion of oil palm plantations, particularly in SE Asia. Oil palm plantations in Sumatra, Indonesia, together with those in Kalimantan, are responsible for half of the world's palm oil production. Available studies point to plantations being large carbon dioxide (CO2) sinks due to the high photosynthetic rates of oil palm as a result of high fertilizer inputs, especially in large-scale plantations. However, methane (CH4) uptake in the soil of oil palm plantations is reduced and soil nitrous oxide (N2O) emissions increased right after nitrogen (N) fertilization. Greenhouse gas (GHG) budgets at the ecosystem level are still missing, and the few available information was derived from mature plantations, pointing to a lack of knowledge on the changes of these GHG budgets with plantation age. With the aim of quantifying CO2, CH4 and N2O fluxes during the non-productive and productive phases of oil palm cultivation, an eddy covariance (EC) tower was installed in a 2-year old (non-productive) oil palm plantation and was subsequently moved to a 12-year old (productive) plantation. Both sites were on Acrisol soils and were located in Jambi province, Sumatra. Chamber-based measurements of soil GHG fluxes were also carried out along the EC footprint. Net ecosystem exchange (NEE), based on EC measurement, showed that the non-productive plantation was a strong CO2 source (990 g C m-2 yr-1) whereas the productive plantation was a CO2 sink (-790 g C m-2 yr-1). For CH4 fluxes, both plantations showed similar soil CH4 uptake that led to a small carbon sink of (~1.3 g C m-2 yr-1). Soil N2O fluxes were high in the productive plantation (3.26 ± 1.73 kg N ha-1 yr-1), as measurements were carried out in a plantation with high fertilization rates. In the non-productive plantation, soil N2O fluxes were lower and were associated with fertilization events. Our results show that the global warming potential of a non-productive oil

  1. Soil processes evolved by the establishment of tree plantations on croplands/grasslands - evaluation of afforestation effect on the Great Plain (Hungary)

    NASA Astrophysics Data System (ADS)

    Balog, Kitti; Szabó, András; Gribovszki, Zoltán; Tóth, Tibor

    2016-04-01

    In Hungary, there was a great increase in the acreage of forested areas during the last century (1.1 to 1.8 million ha). Most of the plantations were established on non-profitable grasslands/croplands (National Forest Strategy, 2009). The forests affect hydrologic and climatic elements of the physical habitat and induce alterations in the soil properties, as well. Soil and groundwater of 70 plantations (Poplar, Common oak and Black locust) and nearby control plots (grassland/cropland) - representing former land use - were investigated over the Great Hungarian Plain. Sampling sites were located by a gradient of climatic water balance, initial water table depth and salinity, soil layering, tree species and plantation age. Short- and long-term effects in groundwater levels (GWL) were found under the woody vegetation. GWL depression evolved beneath forests (poplar and oak provably) compared to control, in 78.8% of the cases. GWL depression was the most significant in the growing season, then the difference between GWLs decreased. Since evapotranspiration (ET) is the main driving force for water consumption of trees, and the ET of trees can be three times higher than that of the grassy control in the growing season, greater (ground)water uptake could be measured, giving rise to higher GWL depression. Short-term effect of the plantation was the daily fluctuation of GWL in the woods that can be twice as much as that of the control. Water uptake is influenced by the type of the groundwater zone (recharge/discharge), where the sample area is located, and by tree species (diverse water demands). Afforestation raised the salt content of the groundwater slightly. In 52.9 % of the cases, salt content of groundwater was higher under the forest, than under the control. Below the forests, salts concentrated in the soil profile and formed a salt accumulation zone surrounding the root zone. In 52.9 % of the cases, salts accumulated in the profile: in the subsoil under the trees (3

  2. Natural vegetation restoration is more beneficial to soil surface organic and inorganic carbon sequestration than tree plantation on the Loess Plateau of China.

    PubMed

    Jin, Zhao; Dong, Yunshe; Wang, Yunqiang; Wei, Xiaorong; Wang, Yafeng; Cui, Buli; Zhou, Weijian

    2014-07-01

    Natural vegetation restoration and tree plantation are the two most important measures for ecosystem restoration on the Loess Plateau of China. However, few studies have compared the effects of the two contrasting measures on soil organic and inorganic carbon (SOC and SIC) sequestration or have further used SOC and SIC isotopes to analyze the inherent sequestration mechanism. This study examined a pair of neighboring small watersheds with similar topographical and geological backgrounds. Since 1954, natural vegetation restoration has been conducted in one of these watersheds, and tree plantation has been conducted in the other. The two watersheds have now formed completely different landscapes (naturally restored grassland and artificial forestland). Differences in soil bulk density, SOC and SIC content and storage, and SOC and SIC δ(13)C values were investigated in the two ecosystems in the upper 1m of the soil. We found that SOC storage was higher in the grassland than in the forestland, with a difference of 14.90 Mg ha(-1). The vertical changes in the δ(13)CSOC value demonstrated that the two ecosystems have different mechanisms of soil surface organic carbon accumulation. The SIC storage in the grassland was lower than that in the forestland, with a difference of 38.99 Mg ha(-1). The δ(13)CSIC values indicated that the grassland generates more secondary carbonate than the forestland and that SIC was most likely transported to the rivers from the grassland as dissolved inorganic carbon (DIC). The biogeochemical characteristics of the grassland were favorable for the formation of bicarbonate. Thus, more DIC derived from the dissolution of root and microbial respired CO2 into soil water could have been transported to the rivers through flood runoff. It is necessary to study further the transportation of DIC from the grassland because this process can produce a large potential carbon sink. PMID:24747253

  3. [Effects of litterfall and root input on soil physical and chemical properties in Pinus massoniana plantations in Three Gorges Reservoir Area, China].

    PubMed

    Ge, Xiao-Gai; Huang, Zhi-Lin; Cheng, Rui-Mei; Zeng, Li-Xiong; Xiao, Wen-Fa; Tan, Ben-Wang

    2012-12-01

    An investigation was made on the soil physical and chemical properties in different-aged Pinus massoniana plantations in Three Gorges Reservoir Area under effects of litterfall and roots. The annual litter production in mature stand was 19.4% and 65.7% higher than that in nearly mature and middle-aged stands, respectively. The litter standing amount was in the sequence of mature stand > middle-aged stand > nearly mature stand, while the litter turnover coefficient was in the order of nearly mature stand (0.51) > mature stand (0.40) > middle-aged stand (0.36). The total root biomass, live root biomass, and dead root biomass were the highest in middle-aged stand, and the lowest in nearly mature stand. In middle-aged stand, soil total porosity was the highest, and soil bulk density was the lowest. Soil organic matter and total nitrogen contents were in the order of mature stand > middle-aged stand > nearly mature stand, soil nitrate nitrogen occupied a larger proportion of soil mineral N in nearly mature stand, while ammonium nitrogen accounted more in middle-aged and mature stands. In nearly mature stand, litter production was moderate but turnover coefficient was the highest, and soil nutrient contents were the lowest. In middle-aged stand, root biomass and soil total porosity were the highest, and soil bulk density were the lowest. In mature stand, root biomass was lower while soil nutrient contents were the highest. The increase of root biomass could improve soil physical properties. PMID:23479870

  4. Influence of seedling roots, environmental factors and soil characteristics on soil CO2 efflux rates in a 2-year-old loblolly pine (Pinus taeda L.) plantation in the Virginia Piedmont.

    PubMed

    Pangle, R E; Seiler, J

    2002-01-01

    To understand the role of managed forests in carbon sequestration an understanding of factors controlling soil CO2 efflux will be necessary. This study examined the influence of seedling roots, environmental factors, nutrient availability, and soil characteristics on soil CO2 efflux patterns in a 2-year-old pine plantation in the Virginia Piedmont. Efflux rates were measured both near the base of seedlings and midway between rows in plots that had received fertilization and mulch treatments in a factorial combination. Soil CO2 efflux rates were consistently higher near the base of seedlings, fertilization increased seedling growth with no significant effect on rates. and mulching increased winter efflux rates. In a regression analysis of seasonal soil CO2 efflux, soil temperature explained 42.2% of the variance followed by the interaction of soil temperature and moisture and of soil temperature and plot position, which together explained an additional 9.8% of the observed variance in seasonal rates. During March 2000 measurements, the spatial pattern of soil CO2 efflux between plots was most influenced by differences in soil nitrogen and pine root biomass. Furthermore, spatial differences observed in mean annual efflux rates were found to be highly influenced by the amount of soil coarse fragments in the upper soil profile. PMID:11833922

  5. Recovery of a soil degraded by deep excavation using plantation of tree species and a cellulose by-product as amendment

    NASA Astrophysics Data System (ADS)

    Guimarães Giácomo, Rômulo; Alves, Marlene Cristina; Paz-Ferreiro, Jorge

    2014-05-01

    Organic by-products obtained from the cellulose industry have been used as costs effective fertilizers in agricultural and forest soils and also as amendments for recovery of abandoned land. The construction of a power plant in the Paraná River (Brazil) motivates the deep excavation of a soil profile under native forest. Once exposed, the saprolite beneath the natural soil was abandoned, without any reclamation measure. The land left after engineering works was a harsh environment, where secondary vegetation hardly or not at all recovered. The objective of this study was to tests the efficiency of recycling a composted product obtained from cellulose waste to reclaim the abandoned saprolite material. A field trial was carried out following a classical split-split plot experimental design. In this design plantations plantations of Eucalyptus urograndis (a hybrid Eucalyptus species, considered here as exotic) and Mabea fistulifera (a native species) were the main plots. Within each main plot, subplots were six fertilizer treatments including an external control treatment, without any intervention, a control treatment, without fertilization, a mineral fertilizer treatment and three treatments amended with compost from cellulose applied at the rates of 10, 15 and 20 Mg ha-1. There were four replications per treatment. The recovery of the soil profile under the different treatments studied was assessed by indices obtained from analysis of soil physical and chemical properties. Variables such as tree species development, litter and plant debris fall, return of nutrients from vegetation to soil and epigeal fauna were also characterized. Increasing dose of amendment with cellulose by-product showed a trend to improve water infiltration and soil resistance to penetration. Treatment with 20 Mg ha-1of cellulose compost showed the highest nutrient availability, but also exhibited an important increase in soil pH. The greatest development of planted trees was recorded in the

  6. Hydraulic Redistribution of Soil Water in a Drained Loblolly Pine Plantation: Quantifying Patterns and Controls over Soil-to-Root and Canopy-to-Atmosphere Interactions

    NASA Astrophysics Data System (ADS)

    Domec, J.; Noormets, A.; King, J. S.; Sun, G.; McNulty, S. G.; Gavazzi, M. J.; Strickland, S.; Boggs, J. L.

    2007-12-01

    The conversion of wetlands to intensively managed forest lands in eastern North Carolina is widespread and the consequences on water and carbon balances are not well studied. Quantification of evapotranspiration (ET), tree transpiration and their biophysical regulation are needed for assessing forest water management options. We characterized vertical variation in the diurnal and seasonal soil volumetric water content at 10 cm intervals to evaluate changes in water availability for root uptake and monitored eddy covariance ET and tree transpiration (sap flux) in a drained Loblolly pine (Pinus taeda L.) plantation. We also quantified the magnitude of hydraulic redistribution (HR), the passive movement of soil water from deep to shallow roots, to identify factors affecting the seasonal dynamics of root water uptake, root and plant water potentials and stomatal conductance. Soil water content varied with soil depth and total water use from the upper 1m peaked between 4 and 6.5 mm/day during the growing season and was strongly correlated and similar to ET (ET represented 90-95% of total water depletion). After periods of more than 10 days without rain, water extraction shifted to the deeper layers, and recharge from HR approached 0.5 mm/day in the upper 60 cm. However, the upper 30cm accounted for 40% of total water depletion from the upper 1m at peak water uptake (>4 mm/day), and increased to 65% during days of low water uptake (<2 mm/day), illustrating the contribution of deeper roots to water uptake during days of high evaporative demand. This result was supported by the fact that deep roots (from 30-50cm) accounted for 65% of the total water redistributed. Because of stomatal regulation to prevent water potentials from reaching critical values that would cause significant loss of tree hydraulic conductivity, maximum tree transpiration during high evaporative demand remained constant at around 3 mm/day. Tree transpiration represented on average 60% of ET. However

  7. Change in lignin content during litter decomposition in tropical forest soils (Congo): comparison of exotic plantations and native stands

    NASA Astrophysics Data System (ADS)

    Bernhard-Reversat, France; Schwartz, Dominique

    1997-09-01

    Fast-growing tree plantations are being extended in tropical countries resulting in new forest ecosystems, the functioning of which is yet not well known. In particular, few data are available concerning lignin decay rate. Lignin, nitrogen and tannin contents of fresh and decaying litter were measured in natural rain forest and in planted stands of Eucalyptus hybrids. Acacia mangium and A. auriculiformisin Congo, together with litter-fall and forest-floor accumulation. Lignin evolution in aging litter exhibited different patterns. Lignin was accumulated under Eucalyptus plantation, but disappeared under natural forest, and was intermediate under Acaciaplantations. The relationships with decomposition rates and lignin degradation factors, such as white rot fungi and termites, are also discussed.

  8. The influence of liming on soil chemical properties and on the alleviation of manganese and copper toxicity in Juglans regia, Robinia pseudoacacia, Eucalyptus sp. and Populus sp. plantations.

    PubMed

    Chatzistathis, T; Alifragis, D; Papaioannou, A

    2015-03-01

    Juglans regia, Robinia pseudoacacia, Eucalyptus sp. and Populus sp. plantations, suffering from Mn and Cu toxicity, were limed in order to reduce Cu and Mn solubility in soil. The purposes of the present work were: i) to study the changes in soil chemical properties after the addition of CaCO3, ii) to investigate the influence of liming on the reduction of Mn and Cu toxicity. After the addition of CaCO3 (three applications, during three successive years), pH and CaCO3 content were significantly increased, while organic C and N were significantly reduced. Exchangeable Ca concentrations have been slightly, or significantly, increased, while those of Mg have been decreased; in addition, ratios Ca/Mg and C/N have been significantly increased after liming. Impressive reductions of DTPA extractable Cu and Mn concentrations (more than 10 times in most cases) were recorded. It was also found that trees without Mn and Cu toxicity symptoms (healthy tress) before liming did not have, in many cases, significantly greater leaf Mn, Cu and Fe concentrations, than trees after soil liming (all the trees were healthy). This probably happened because excess Mn and Cu quantities had been accumulated into their root system. Finally, leaf Mn, Cu and Zn concentrations of trees suffering from toxicity were significantly decreased after soil liming, while leaf Fe concentrations, in all the plant species studied, were increased. PMID:25485934

  9. Residue determination and levels of glyphosate in surface waters, sediments and soils associated with oil palm plantation in Tasik Chini, Pahang, Malaysia

    NASA Astrophysics Data System (ADS)

    Mardiana-Jansar, K.; Ismail, B. S.

    2014-09-01

    Levels of glyphosate and its main metabolite were determined in surface water, soil and sediment samples from an oil palm plantation area located at Tasik Chini, Pahang, Malaysia. The optimization analytical method has been developed for the determination of glyphosate herbicide and its metabolite amino-methyl-phosphonic acid (AMPA) in surface waters to a level of 0.1μg/L, while in sediments and soils to a level of 0.5μg/g with a good linearity in the calibration range of 1-100μg/L. The procedure involves a pre-columnderivatization step with 9-fluorenyl-methyl-chloroformate (FMOC-Cl) yielding highly fluorescent derivatives of the analytes which can be determined by HPLC with fluorescence detection. In the field, levels of glyphosate in surface waters ranges from not detected to 1.0mg/L, while in soils and sediments were from not detected to 6.0mg/kg. For AMPA, the residues in surface waters were between not detected to 2.0mg/L, while in soil and sediment samples were from not detected to 5mg/kg. This variation of glyphosate and AMPA levels depended directly on time of pesticide application and the season.

  10. Role and Variation of the Amount and Composition of Glomalin in Soil Properties in Farmland and Adjacent Plantations with Reference to a Primary Forest in North-Eastern China

    PubMed Central

    Wang, Qiong; Wang, Wenjie; He, Xingyuan; Zhang, Wentian; Song, Kaishan; Han, Shijie

    2015-01-01

    The glycoprotein known as glomalin-related soil protein (GRSP) is abundantly produced on the hyphae and spores of arbuscular mycorrhizal fungi (AMF) in soil and roots. Few studies have focused on its amount, composition and associations with soil properties and possible land-use influences, although the data hints at soil rehabilitation. By choosing a primary forest soil as a non-degraded reference, it is possible to explore whether afforestation can improve degraded farmland soil by altering GRSP. In this paper, close correlations were found between various soil properties (soil organic carbon, nitrogen, pH, electrical conductivity (EC), and bulk density) and the GRSP amount, between various soil properties and GRSP composition (main functional groups, fluorescent substances, and elements). Afforestation on farmland decreased the EC and bulk density (p < 0.05). The primary forest had a 2.35–2.56-fold higher GRSP amount than those in the plantation forest and farmland, and GRSP composition (tryptophan-like and fulvic acid-like fluorescence; functional groups of C–H, C–O, and O–H; elements of Al, O, Si, C, Ca, and N) in primary forest differed from those in plantation forest and farmland (p < 0.05). However, no evident differences in GRSP amount and composition were observed between the farmland and the plantation forest. Our finding highlights that 30 years poplar afforestation on degraded farmland is not enough to change GRSP-related properties. A longer period of afforestation with close-to-nature managements may favor the AMF-related underground recovery processes. PMID:26430896

  11. Soil CO2 Efflux and Its Components Responded Differently to Throughfall Exclusion and Fertilization in a Loblolly Pine (Pinus taeda) Plantation

    NASA Astrophysics Data System (ADS)

    Yang, J.; Luedtke, C.; Akers, K.; McGuire, M.; Aubrey, D. P.; Teskey, R. O.

    2014-12-01

    Soil CO2 efflux (RS) is an important component of forest ecosystem carbon budgets and net ecosystem CO2 exchange, but little is known about how RS and its components respond to decreasing soil moisture and changes in soil fertility. The experiment design was a 2 X 2 factorial combination of fertilization (2 levels) and precipitation (throughfall exclusion, 2 levels) replicated in four blocks. We measured RS along with soil temperature (Ts) and soil moisture (WS) from 2012 to 2014 in a loblolly pine plantation in Washington, GA. The autotrophic (RA) and heterotrophic (RH) components of soil CO2 efflux were separated using trenched plots. Our objectives were to (1) quantify impacts of throughfall exclusion and fertilization on RS and its components (RA, RH).and (2) determine soil CO2efflux and its components individually response to environmental factors and biological factors in throughfall exclusion and fertilization treatments. Annual mean RS was 2.11, 1.73, 2.09 and 1.92 for treatments of control, fertilization, throughfall exclusion and combination of fertilization and throughfall exclusion, respectively, from 2012 to 2013. The apparent Q10 for RS was 2.26, 2.25, 2.12 and 2.35 in the four treatments, respectively. There were no significant differences in RS among treatments except between the Ws treatments. However, there was slight reduction in RS and RA in fertilization and the fertilization plus throughfall exclusion treatment. In all treaments, Ts explained more than 80% of variation in RS. The contribution of CO2-derived from ectomycorrhizal hyphae was less than 15%. RS and RH was better predicted by TS in the dormant season than the growing season, indicating that additional factors such as root growth and photosynthesis became more important contributors to RS during the growing season. Fertilization slightly decreased RS mainly from a decrease in RH. Throughfall exclusion increased the contribution of RA to RS. We concluded that soil moisture had more

  12. Managing declining yields from ageing tea plantations.

    PubMed

    Kibblewhite, Mark G; Prakash, Sudhir; Hazarika, Mridul; Burgess, Paul J; Sakrabani, Ruben

    2014-06-01

    Strong growth in the demand for tea requires further increases in the productivity of plantations. Declining or stagnant yields are commonly observed in older plantations. Possible controlling factors for yield decline are reviewed including ageing of plants, chronic disease and sub-optimal soil conditions such as excess soil acidity and low soil organic matter. Management options for addressing these factors are evaluated, including replanting. A systematic approach to decision-making about replanting is presented. Practice for replanting is reviewed and it is concluded that evidence to support a general case for replanting is limited, unless based on the introduction of more productive clones and/or better plant spacing. PMID:24464583

  13. Distinct bacterial community structure of 3 tropical volcanic soils from banana plantations contaminated with chlordecone in Guadeloupe (French West Indies).

    PubMed

    Mercier, Anne; Dictor, Marie-Christine; Harris-Hellal, Jennifer; Breeze, Dominique; Mouvet, Christophe

    2013-08-01

    In the French West Indies (FWI), the soil, andosols, ferralsols and nitisols, is highly polluted by chlordecone, although this organochlorine insecticide extensively applied to banana crops has been banned for 20years. This contamination has led to a major human health concern inducing the need for remediation of the contaminated soils. Work was conducted to help to evaluate the impact of remediation processes on the microbial communities from these soils. Microbial biomass was estimated after direct DNA extraction from three chlordecone-contaminated soils (an andosol, a ferralsol and a nitisol) and the bacterial community analyzed using t-RFLP. The FWI volcanic andosol was particularly recalcitrant to usual direct DNA extraction protocols hampering analysis of soil microbial communities until now, in contrast with the 2 other soils. For the first time, DNA was directly extracted from a FWI andosol based on yeast RNA addition at the lysis step. Differences in microbial biomass were thus observed between the 3 FWI soils. Moreover, the bacterial community structure was significantly distinct from each other's and related to soil physico-chemical characteristics. Interestingly, differences in bacterial diversity could not be exclusively attributed to the level of chlordecone contamination. PMID:23706897

  14. Inter-annual variation in the response of leaf-out onset to soil moisture increase in a teak plantation in northern Thailand.

    PubMed

    Yoshifuji, Natsuko; Igarashi, Yasunori; Tanaka, Nobuaki; Tanaka, Katsunori; Sato, Takanori; Tantasirin, Chatchai; Suzuki, Masakazu

    2014-11-01

    To understand the impact of inter-annual climate change on vegetation-atmosphere mass and energy exchanges, it has become necessary to explore changes in leaf-out onset in response to climatic fluctuations. We examined the response of leaf-out and transpiration onset dates to soil moisture in a teak plantation in northern Thailand based on a 12-year leaf area index and sap flow measurements. The date of leaf-out and transpiration onset varied between years by up to 40 days, and depended on the initial date when the relative extractable water in a soil layer of 0-0.6 m (Θ) was greater than 0.2 being consistent with our previous results. Our new finding is that the delay in leaf-out and transpiration onset relative to the initial date when Θ > 0.2 increases linearly as the initial date on which Θ > 0.2 becomes earlier. The delay spans about 20 days in years when Θ > 0.2 occurs in March (the late dry season)-much earlier than usual because of heavy pre-monsoon rainfalls-while there is little delay in years when Θ > 0.2 occurs in May. This delay indicates the influence of additional factors on leaf-out onset, which controls the delay in the response of leaf-out to soil moisture increase. The results increased our knowledge about the pattern and extent of the changes in leaf phenology that occur in response to the inter-annual climate variation in tropical regions, where, in particular, such research is needed. PMID:24469544

  15. Inter-annual variation in the response of leaf-out onset to soil moisture increase in a teak plantation in northern Thailand

    NASA Astrophysics Data System (ADS)

    Yoshifuji, Natsuko; Igarashi, Yasunori; Tanaka, Nobuaki; Tanaka, Katsunori; Sato, Takanori; Tantasirin, Chatchai; Suzuki, Masakazu

    2014-01-01

    To understand the impact of inter-annual climate change on vegetation-atmosphere mass and energy exchanges, it has become necessary to explore changes in leaf-out onset in response to climatic fluctuations. We examined the response of leaf-out and transpiration onset dates to soil moisture in a teak plantation in northern Thailand based on a 12-year leaf area index and sap flow measurements. The date of leaf-out and transpiration onset varied between years by up to 40 days, and depended on the initial date when the relative extractable water in a soil layer of 0-0.6 m (Θ) was greater than 0.2 being consistent with our previous results. Our new finding is that the delay in leaf-out and transpiration onset relative to the initial date when Θ > 0.2 increases linearly as the initial date on which Θ > 0.2 becomes earlier. The delay spans about 20 days in years when Θ > 0.2 occurs in March (the late dry season)—much earlier than usual because of heavy pre-monsoon rainfalls—while there is little delay in years when Θ > 0.2 occurs in May. This delay indicates the influence of additional factors on leaf-out onset, which controls the delay in the response of leaf-out to soil moisture increase. The results increased our knowledge about the pattern and extent of the changes in leaf phenology that occur in response to the inter-annual climate variation in tropical regions, where, in particular, such research is needed.

  16. Degradation of Triazine-2-(14)C Metsulfuron-Methyl in Soil from an Oil Palm Plantation.

    PubMed

    Ismail, B S; Eng, O K; Tayeb, M A

    2015-01-01

    Triazine-2-(14)C metsulfuron-methyl is a selective, systemic sulfonylurea herbicide. Degradation studies in soils are essential for the evaluation of the persistence of pesticides and their breakdown products. The purpose of the present study was to investigate the degradation of triazine-2-(14)C metsulfuron-methyl in soil under laboratory conditions. A High Performance Liquid Chromatograph (HPLC) equipped with an UV detector and an on-line radio-chemical detector, plus a Supelco Discovery column (250 x 4.6 mm, 5 μm), and PRP-1 column (305 x 7.0 mm, 10 μm) was used for the HPLC analysis. The radioactivity was determined by a Liquid Scintillation Counter (LSC) in scintillation fluid. The soil used was both sterilized and non-sterilized in order to observe the involvement of soil microbes. The estimated DT50 and DT90 values of metsulfuron-methyl in a non-sterile system were observed to be 13 and 44 days, whereas in sterilized soil, the DT50 and DT90 were 31 and 70 days, respectively. The principal degradation product after 60 days was CO2. The higher cumulative amount of (14)CO2 in (14)C-triazine in the non-sterilized soil compared to that in the sterile system suggests that biological degradation by soil micro-organisms significantly contributes to the dissipation of the compound. The major routes of degradation were O-demethylation, sulfonylurea bridge cleavage and the triazine "ring-opened." PMID:26437264

  17. Degradation of Triazine-2-14C Metsulfuron–Methyl in Soil from an Oil Palm Plantation

    PubMed Central

    B. S., Ismail

    2015-01-01

    Triazine-2-14C metsulfuron–methyl is a selective, systemic sulfonylurea herbicide. Degradation studies in soils are essential for the evaluation of the persistence of pesticides and their breakdown products. The purpose of the present study was to investigate the degradation of triazine-2-14C metsulfuron–methyl in soil under laboratory conditions. A High Performance Liquid Chromatograph (HPLC) equipped with an UV detector and an on-line radio-chemical detector, plus a Supelco Discovery column (250 x 4.6 mm, 5 μm), and PRP–1 column (305 x 7.0 mm, 10 μm) was used for the HPLC analysis. The radioactivity was determined by a Liquid Scintillation Counter (LSC) in scintillation fluid. The soil used was both sterilized and non-sterilized in order to observe the involvement of soil microbes. The estimated DT50 and DT90 values of metsulfuron-methyl in a non-sterile system were observed to be 13 and 44 days, whereas in sterilized soil, the DT50 and DT90 were 31 and 70 days, respectively. The principal degradation product after 60 days was CO2. The higher cumulative amount of 14CO2 in 14C- triazine in the non-sterilized soil compared to that in the sterile system suggests that biological degradation by soil micro-organisms significantly contributes to the dissipation of the compound. The major routes of degradation were O-demethylation, sulfonylurea bridge cleavage and the triazine “ring-opened.” PMID:26437264

  18. Hemipteran diversity in Endau-Rompin plantation

    NASA Astrophysics Data System (ADS)

    Bakri, Asraf; Rahim, Faszly

    2015-09-01

    Study on hemipteran at Endau Rompin Plantation (LER), Pahang was conducted at oil palm plantation planted at different type of soils. The aim of the study was to determine hemipteran diversity in oil palm ecosystem. Sampling was done from April 2012 to September 2012 by using Malaise and impact traps. Cicadellidae was the most abundance and dominance family with 105 individuals and 6 species (=morphospecies) recorded. The rarefaction curve becomes flatter to the right indicating a reasonable number of individual samples have been taken. Peat area show high Shannon index and Margalef index values compared to clay area.There were significant differences in hemipteran community between three type of soils (χ2=98.751,df=58,p<0.05). As such, hemipteran abundance in oil palm plantation is affected by the type of soil.

  19. Rubber plantations act as water pumps in tropical China

    NASA Astrophysics Data System (ADS)

    Tan, Zheng-Hong; Zhang, Yi-Ping; Song, Qing-Hai; Liu, Wen-Jie; Deng, Xiao-Bao; Tang, Jian-Wei; Deng, Yun; Zhou, Wen-Jun; Yang, Lian-Yan; Yu, Gui-Rui; Sun, Xiao-Min; Liang, Nai-Shen

    2011-12-01

    Whether rubber plantations have the role of water pumps in tropical Southeast Asia is under active debate. Fifteen years (1994-2008) of paired catchments water observation data and one year paired eddy covariance water flux data in primary tropical rain forest and tropical rubber plantation was used to clarify how rubber plantation affects local water resources of Xishuangbanna, China. Both catchment water observations and direct eddy covariance estimates indicates that more water was evapotranspired from rubber plantation (1137 mm based on catchment water balance, 1125 mm based on eddy covariance) than from the rain forest (969 mm based on catchment water balance, 927 mm based on eddy covariance). Soil water storage during the rainy season is not sufficient to maintain such high evapotranspiration rates, resulting in zero flow and water shortages during the dry season in the rubber plantation. Therefore, this study supports the idea that rubber plantations act as water pumps as suggested by local inhabitants.

  20. Growth, biomass allocation and photosynthetic responses are related to intensity of root severance and soil moisture conditions in the plantation tree Cunninghamia lanceolata.

    PubMed

    Dong, Tingfa; Duan, Baoli; Zhang, Sheng; Korpelainen, Helena; Niinemets, Ülo; Li, Chunyang

    2016-07-01

    We employed the warm temperate conifer Cunninghamia lanceolata (Lamb.) Hook. as a model of plantation forest species to investigate ecophysiological responses to root treatments (control (0%), and ∼25, 50 or 75% of the initial root mass) under well-watered and water-limited conditions. Our results indicated that total root dry mass accumulation was negatively associated with the severity of root pruning, but there was evidence of multiple compensatory responses. The plants exhibited higher instantaneous and long-term (assessed by carbon isotope composition, δ(13)C) water-use efficiency in pruning treatments, especially under low water availability. Root pruning also increased the fine root/total root mass ratio, specific root length and fine root vitality in both water availability treatments. As a result of the compensatory responses, under well-watered conditions, height, stem dry mass accumulation, leaf/fine root biomass ratio (L/FR), transpiration rate, photosynthetic capacity and photosynthetic nitrogen-use efficiency (EN) were the highest under 25% pruning. Yet, all these traits except L/FR and foliage nitrogen content were severely reduced under 75% pruning. Drought negatively affected growth and leaf gas exchange rates, and there was a greater negative effect on growth, water potential, gas exchange and EN when >25% of total root biomass was removed. The stem/aboveground mass ratio was the highest under 25% pruning in both watering conditions. These results indicate that the responses to root severance are related to the excision intensity and soil moisture content. A moderate root pruning proved to be an effective means to improve stem dry mass accumulation. PMID:27122365

  1. Uptake and Hydraulic Redistribution of Soil Water in a Natural Forested Wetland and in two Contrasting Drained Loblolly Pine Plantations: Quantifying Patterns over Soil-to-Root and Canopy-to-Atmosphere Interactions

    NASA Astrophysics Data System (ADS)

    Domec, J.; King, J. S.; Noormets, A.; Sun, G.; McNulty, S. G.; Gavazzi, M. G.; Treasure, E.; Boggs, J. L.

    2009-05-01

    The conversion of wetlands to intensively managed forest lands in eastern North Carolina is widespread and the consequences on water and carbon balances are not well studied. Quantification of evapotranspiration (ET), tree transpiration and their biophysical regulation are needed for assessing forest water management options. We characterized vertical variation in the diurnal and seasonal soil volumetric water content at 10 cm intervals to evaluate changes in water availability for root uptake and monitored eddy covariance ET and tree transpiration (sap flux) in three contrasting loblolly pine (Pinus taeda L.) stands. Those stands included a 50- yr-old wetland natural regeneration (NG), a 17-yr-old drained mid-rotation plantation (MP) and a 5-yr-old drained plantation (YP) in eastern North Carolina. We also quantified the magnitude of hydraulic redistribution (HR), the passive movement of soil water from deep to shallow roots, to identify factors affecting the seasonal dynamics of root water uptake, root and plant water potentials and stomatal conductance. In NG, soil water content was always at full saturation and total tree water use peaked between 6-7 mm/day, and this stand was used as reference. In MP, soil water content varied with soil depth and total water use from the upper 1m peaked between 4 and 6.5 mm/day during the growing season and was strongly correlated and similar to ET (ET represented 90-95% of total water depletion). In YP, soil water used was limited to the upper 30 cm and was strongly affected by summer drought by declining progressively from 0.9 mm/day in spring to 0.4 m/day in September. After periods of more than 10 days without rain, water extraction in MP shifted to the deeper layers, and recharge from HR approached 20% of ET. During days of high evaporative demand, water use in MP was comparable to NG thanks to HR and to the contribution of deeper roots to water uptake. In YP, HR never contributed for more than 8% of ET. There was no HR

  2. How to improve fertility of African soils? Leguminous fallows (Cameroon), addition of farmyard manure and mineral fertilizer (Kenya), organic residues management and introduction of N2 fixing species in forest plantations (Congo).

    NASA Astrophysics Data System (ADS)

    Koutika, Lydie-Stella; Mareschal, Louis; Mouanda, Cadeau; Epron, Daniel

    2014-05-01

    Most of African soils are inherently infertile and poor in nutrients mainly nitrogen and phosphorus. Several practices are used to improve soil fertility, increase productivity and ensure their sustainability. Soil fertility in the leguminous fallows was evaluated through particulate organic matter (POM), the more active part of soil organic matter (SOM) in Cameroon. The combination of mineral and organic (manure) fertilizers increased microbial P biomass allowing the release of P along the plant growing period in the Kenyan soils. Organic residues management and introduction of nitrogen fixing species (Acacia) were used to improve soil fertility and sustain forest productivity on the coastal plains of Congo. SOM fractionation was made under Pueraria, Mucuna fallows and natural regrowth mainly Chromolaena and under 3 forest plantation treatments installed in previous savanna: 1) no input, 2) normal input, and 3) double input of organic residues. Microbial P biomass and sequential P fractionation were evaluated in high and low P fixing soils. N, C, available P and pH were determined on soil sampled in acacia (100A), eucalypt (100E) and mixed-species (50A:50E) stands. N and P were determined in aboveground litters and in leaves, bark and wood of trees. The two leguminous fallows increased N content in POM fractions i.e., N >1% for Pueraria and Mucuna against N<1% for natural regrowth in the 0-0.10m depth, probably through N input from N2 fixation from the atmosphere (Cameroon).The addition of mineral fertilizers and farmyard manure increases P biomass (4.8 after 2 weeks to 15.2 after 16 weeks), and then decreased to 9.7 mg P g-1 soil (week 32). It also changes the P Hedley fractions partition in the high P fixing Kenyan soil (0-0.10m). After two rotations (14 years), SOM mineralization was the highest in the double input of organic residues treatment (low coarse POM 5.6 g kg-1 of soil and high organo-mineral fraction (OMF) 115 g kg-1 of soil). The introduction of A

  3. Space Farm 7 Belvedere Plantation

    NASA Video Gallery

    A space theme maze and NASA exhibits turned a Virginia farm into an out-of-this-world experience for families and visitors at the Belvedere Plantation in Fredericksburg, Virginia. Belvedere Plantat...

  4. Hydrological impact of Eucalyptus plantation in India

    NASA Astrophysics Data System (ADS)

    Calder, Ian R.; Hall, Robin L.; Prasanna, K. T.

    1993-10-01

    A brief review is given of the results of hydrological studies carried out in southern India on the effects of plantations of Eucalyptus and other fast growing exotic tree species on water resources, erosion and soil nutrients at sites of differing rainfall and soil depth in Karnataka. New results on the impacts of the plantations on raindrop-induced erosion and preliminary results from studies that are aimed at improving the water use efficiency of the plantations are also presented. The erosion studies indicate that soil detachment resulting from net rainfall beneath Eucalyptus camaldulensis will be greater than beneath Pinus caribaea but less than that beneath the indigenous species, Tectona grandis. The water use efficiency studies, which make use of a controlled environment facility, have confirmed that in the dry zone of southern India water availability is the principal limiting factor on growth although, when water is available, nutrient limitations become important. Removal of both water and nutrient stress results typically in a fivefold increase in volume growth for the first year of growth.

  5. The causes and consequences of deeper rooting distributions under elevated [CO2]: Improved understanding of root-soil interactions from a Free-Air CO2 Enrichment experiment in a sweetgum plantation (Invited)

    NASA Astrophysics Data System (ADS)

    Iversen, C. M.; Childs, J.; Norby, R. J.

    2013-12-01

    Belowground processes are increasingly recognized as an important foundation for ecosystem responses to rising atmospheric [CO2]. Elevated [CO2] has been shown to increase the proportion of biomass in fine roots, and experimental evidence from a diverse set of forested ecosystems indicates that CO2-enrichment may lead to deeper rooting distributions. Deeper rooting distributions in CO2-enriched forests are likely a result of three interacting factors: (1) increased resource demand, (2) greater carbon (C) available for belowground allocation, and (3) increased competition for scarce resources in shallower soil. Increased production of fine roots at depth in the soil could drive changes in C cycling because fine roots turn over quickly in forests. However, the consequences of increased fine-root proliferation and turnover at depth are still poorly understood; this is in part because belowground research is often truncated at relatively shallow soil depths. We examined soil C dynamics after 12 years of CO2-enrichment and at soil depths to 90 cm in soil pits harvested at the conclusion of the Oak Ridge National Laboratory (ORNL) Free-Air CO2 Enrichment (FACE) located in a sweetgum plantation in eastern Tennessee, USA. We hypothesized that: (1) soil C content would increase in response to elevated [CO2], especially at deeper soil depths where large increases in root production and mortality were observed, and (2) greater C inputs under elevated [CO2] would lead to increased potential C mineralization in long-term laboratory incubations. As we hypothesized, total soil C content under elevated [CO2] was 20% greater throughout the soil profile to 90 cm depth. The CO2 effect was driven by an increase in the C content of the relatively labile particulate organic matter (POM) pool, which is likely derived primarily from fine roots. Contrary to what we hypothesized, we did not observe a significant increase in potential soil C mineralization under elevated [CO2]. While C

  6. Warming reduces the cover and diversity of biocrust-forming mosses and lichens, and increases the physiological stress of soil microbial communities in a semi-arid Pinus halepensis plantation.

    PubMed

    Maestre, Fernando T; Escolar, Cristina; Bardgett, Richard D; Dungait, Jennifer A J; Gozalo, Beatriz; Ochoa, Victoria

    2015-01-01

    Soil communities dominated by lichens and mosses (biocrusts) play key roles in maintaining ecosystem structure and functioning in drylands worldwide. However, few studies have explicitly evaluated how climate change-induced impacts on biocrusts affect associated soil microbial communities. We report results from a field experiment conducted in a semiarid Pinus halepensis plantation, where we setup an experiment with two factors: cover of biocrusts (low [<15%] versus high [>50%]), and warming (control versus a ∼2°C temperature increase). Warming reduced the richness and cover (∼45%) of high biocrust cover areas 53 months after the onset of the experiment. This treatment did not change the ratios between the major microbial groups, as measured by phospholipid fatty acid analysis. Warming increased the physiological stress of the Gram negative bacterial community, as indicated by the cy17:0/16:1ω7 ratio. This response was modulated by the initial biocrust cover, as the increase in this ratio with warming was higher in areas with low cover. Our findings suggest that biocrusts can slow down the negative effects of warming on the physiological status of the Gram negative bacterial community. However, as warming will likely reduce the cover and diversity of biocrusts, these positive effects will be reduced under climate change. PMID:26379642

  7. Warming reduces the cover and diversity of biocrust-forming mosses and lichens, and increases the physiological stress of soil microbial communities in a semi-arid Pinus halepensis plantation

    PubMed Central

    Maestre, Fernando T.; Escolar, Cristina; Bardgett, Richard D.; Dungait, Jennifer A. J.; Gozalo, Beatriz; Ochoa, Victoria

    2015-01-01

    Soil communities dominated by lichens and mosses (biocrusts) play key roles in maintaining ecosystem structure and functioning in drylands worldwide. However, few studies have explicitly evaluated how climate change-induced impacts on biocrusts affect associated soil microbial communities. We report results from a field experiment conducted in a semiarid Pinus halepensis plantation, where we setup an experiment with two factors: cover of biocrusts (low [<15%] versus high [>50%]), and warming (control versus a ∼2°C temperature increase). Warming reduced the richness and cover (∼45%) of high biocrust cover areas 53 months after the onset of the experiment. This treatment did not change the ratios between the major microbial groups, as measured by phospholipid fatty acid analysis. Warming increased the physiological stress of the Gram negative bacterial community, as indicated by the cy17:0/16:1ω7 ratio. This response was modulated by the initial biocrust cover, as the increase in this ratio with warming was higher in areas with low cover. Our findings suggest that biocrusts can slow down the negative effects of warming on the physiological status of the Gram negative bacterial community. However, as warming will likely reduce the cover and diversity of biocrusts, these positive effects will be reduced under climate change. PMID:26379642

  8. Ecosystem Carbon Stock Influenced by Plantation Practice: Implications for Planting Forests as a Measure of Climate Change Mitigation

    PubMed Central

    Liao, Chengzhang; Luo, Yiqi; Fang, Changming; Li, Bo

    2010-01-01

    Uncertainties remain in the potential of forest plantations to sequestrate carbon (C). We synthesized 86 experimental studies with paired-site design, using a meta-analysis approach, to quantify the differences in ecosystem C pools between plantations and their corresponding adjacent primary and secondary forests (natural forests). Totaled ecosystem C stock in plant and soil pools was 284 Mg C ha−1 in natural forests and decreased by 28% in plantations. In comparison with natural forests, plantations decreased aboveground net primary production, litterfall, and rate of soil respiration by 11, 34, and 32%, respectively. Fine root biomass, soil C concentration, and soil microbial C concentration decreased respectively by 66, 32, and 29% in plantations relative to natural forests. Soil available N, P and K concentrations were lower by 22, 20 and 26%, respectively, in plantations than in natural forests. The general pattern of decreased ecosystem C pools did not change between two different groups in relation to various factors: stand age (<25 years vs. ≥25 years), stand types (broadleaved vs. coniferous and deciduous vs. evergreen), tree species origin (native vs. exotic) of plantations, land-use history (afforestation vs. reforestation) and site preparation for plantations (unburnt vs. burnt), and study regions (tropic vs. temperate). The pattern also held true across geographic regions. Our findings argued against the replacement of natural forests by the plantations as a measure of climate change mitigation. PMID:20523733

  9. Ecosystem carbon stock influenced by plantation practice: implications for planting forests as a measure of climate change mitigation.

    PubMed

    Liao, Chengzhang; Luo, Yiqi; Fang, Changming; Li, Bo

    2010-01-01

    Uncertainties remain in the potential of forest plantations to sequestrate carbon (C). We synthesized 86 experimental studies with paired-site design, using a meta-analysis approach, to quantify the differences in ecosystem C pools between plantations and their corresponding adjacent primary and secondary forests (natural forests). Totaled ecosystem C stock in plant and soil pools was 284 Mg C ha(-1) in natural forests and decreased by 28% in plantations. In comparison with natural forests, plantations decreased aboveground net primary production, litterfall, and rate of soil respiration by 11, 34, and 32%, respectively. Fine root biomass, soil C concentration, and soil microbial C concentration decreased respectively by 66, 32, and 29% in plantations relative to natural forests. Soil available N, P and K concentrations were lower by 22, 20 and 26%, respectively, in plantations than in natural forests. The general pattern of decreased ecosystem C pools did not change between two different groups in relation to various factors: stand age (< 25 years vs. > or = 25 years), stand types (broadleaved vs. coniferous and deciduous vs. evergreen), tree species origin (native vs. exotic) of plantations, land-use history (afforestation vs. reforestation) and site preparation for plantations (unburnt vs. burnt), and study regions (tropic vs. temperate). The pattern also held true across geographic regions. Our findings argued against the replacement of natural forests by the plantations as a measure of climate change mitigation. PMID:20523733

  10. Using ecological memory as an indicator to monitor the ecological restoration of four forest plantations in subtropical China.

    PubMed

    Sun, Zhongyu; Ren, Hai; Schaefer, Val; Guo, Qinfeng; Wang, Jun

    2014-12-01

    A large area of plantations has been established worldwide and especially in China. Evaluating the restoration status of these plantations is essential for their long-term management. Based on our previous work, we used an ecological memory (EM) approach to evaluate four 26-year-old plantations that represent four common kinds of plantations in subtropical China, i.e., mixed broad-leaved plantation (MBP), mixed coniferous plantation (MCP), eucalyptus plantation (EP), and mixed legume plantation (MLP). Comparing them with the regional climax community, i.e., monsoon evergreen broad-leaved forest (BF), all four plantations accumulated nearly the same pattern of EM during succession. EM was >50 % for soil minerals, light conditions, soil age, soil animals, and soil microbes. EM was about 25 % for soil pollen and 10 % for birds, soil seed bank, and plant species. The total EM value of the four plantations ranged from 50.96 to 52.54, which indicated that all four plantations were in the regional, natural trajectory of succession and between the early and medium successional stages. The results indicated that natural succession processes are unlikely to be accelerated by planting late-stage tree species without sufficient EM. The results also demonstrated that all four plantations were in positive successional trajectories, and the positive succession dynamics were greater in the MLP and MCP. We suggest that the entire natural succession trajectory be used to evaluate the restoration of a site and that the ultimate restoration target be divided into several milestones along the reference trajectory to monitor progress. Forest restoration may be accelerated by starting with a minimum dynamic unit supporting sufficient EM. PMID:25145281

  11. Significant Increase in Ecosystem C Can Be Achieved with Sustainable Forest Management in Subtropical Plantation Forests

    PubMed Central

    Wei, Xiaohua; Blanco, Juan A.

    2014-01-01

    Subtropical planted forests are rapidly expanding. They are traditionally managed for intensive, short-term goals that often lead to long-term yield decline and reduced carbon sequestration capacity. Here we show how it is possible to increase and sustain carbon stored in subtropical forest plantations if management is switched towards more sustainable forestry. We first conducted a literature review to explore possible management factors that contribute to the potentials in ecosystem C in tropical and subtropical plantations. We found that broadleaves plantations have significantly higher ecosystem C than conifer plantations. In addition, ecosystem C increases with plantation age, and reaches a peak with intermediate stand densities of 1500–2500 trees ha−1. We then used the FORECAST model to simulate the regional implications of switching from traditional to sustainable management regimes, using Chinese fir (Cunninghamia lanceolata) plantations in subtropical China as a study case. We randomly simulated 200 traditional short-rotation pure stands and 200 sustainably-managed mixed Chinese fir – Phoebe bournei plantations, for 120 years. Our results showed that mixed, sustainably-managed plantations have on average 67.5% more ecosystem C than traditional pure conifer plantations. If all pure plantations were gradually transformed into mixed plantations during the next 10 years, carbon stocks could rise in 2050 by 260.22 TgC in east-central China. Assuming similar differences for temperate and boreal plantations, if sustainable forestry practices were applied to all new forest plantation types in China, stored carbon could increase by 1,482.80 TgC in 2050. Such an increase would be equivalent to a yearly sequestration rate of 40.08 TgC yr−1, offsetting 1.9% of China’s annual emissions in 2010. More importantly, this C increase can be sustained in the long term through the maintenance of higher amounts of soil organic carbon and the production of timber

  12. Water use by Pinus radiata trees in a plantation.

    PubMed

    Teskey, R. O.; Sheriff, D. W.

    1996-01-01

    We used the heat-pulse velocity technique to estimate transpirational water use of trees in an experimental 16-year-old Pinus radiata D. Don plantation in South Australia during a 4-month period from November 1993 to March 1994 (spring-summer). Fertilization and other silvicultural treatments during the first 8 years of the plantation produced trees ranging in diameter at a height of 1.3 m from 0.251 to 0.436 m, with leaf areas ranging from 83 to 337 m(2). Daily water use was greater for large trees than for small trees, but transpiration per unit leaf area was nearly identical. Daily transpiration was highly correlated with available soil water in the upper 1 m of soil and weakly correlated with irradiance and air temperature. For the stand (0.4 ha), estimated rates of transpiration ranged from 6.8 to 1.4 mm day(-1) in wet and dry soil conditions, respectively. Total water use by the plantation during the 4-month study period was 346 mm. Water transpired by the trees was about three times that extracted from the upper 1 m of soil. Large trees extracted water from the same soil volume as small trees and did not exhibit a greater potential to extract water from deeper soil when the upper horizons become dry. PMID:14871772

  13. Soil Fungal Cellobiohydrolase I Gene (cbhI) Composition and Expression in a Loblolly Pine Plantation under Conditions of Elevated Atmospheric CO2 and Nitrogen Fertilization

    PubMed Central

    Weber, Carolyn F.; Balasch, Monica Moya; Gossage, Zachary; Porras-Alfaro, Andrea

    2012-01-01

    The simultaneous increase of atmospheric CO2 and nitrogen (N) deposition to terrestrial ecosystems is predicted to alter plant productivity and, consequently, to change the amount and quality of above- and belowground carbon entering forest soils. It is not known how such changes will impact the composition and function of soil fungal communities that play a key role in degrading complex carbon. We sequenced the fungal cellobiohydrolase I gene (cbhI) from soil DNA and cDNA to compare the richness and composition of resident and expressed cbhI genes at a U.S. Department of Energy free air-carbon dioxide enrichment (FACE) site (NC), which had been exposed to elevated atmospheric CO2 and/or N fertilization treatment for several years. Our results provide evidence that the richness and composition of the cellulolytic fungi surveyed in this study were distinct in the DNA- and cDNA-based gene surveys and were dominated by Basidiomycota that have low or no representation in public databases. The surveys did not detect differences in richness or phylum-level composition of cbhI-containing, cellulolytic fungi that correlated with elevated CO2 or N fertilization at the time of sampling. PMID:22467503

  14. Soil fungal cellobiohydrolase I gene (cbhI) composition and expression in a loblolly pine plantation under conditions of elevated atmospheric CO2 and nitrogen fertilization.

    PubMed

    Weber, Carolyn F; Balasch, Monica Moya; Gossage, Zachary; Porras-Alfaro, Andrea; Kuske, Cheryl R

    2012-06-01

    The simultaneous increase of atmospheric CO(2) and nitrogen (N) deposition to terrestrial ecosystems is predicted to alter plant productivity and, consequently, to change the amount and quality of above- and belowground carbon entering forest soils. It is not known how such changes will impact the composition and function of soil fungal communities that play a key role in degrading complex carbon. We sequenced the fungal cellobiohydrolase I gene (cbhI) from soil DNA and cDNA to compare the richness and composition of resident and expressed cbhI genes at a U.S. Department of Energy free air-carbon dioxide enrichment (FACE) site (NC), which had been exposed to elevated atmospheric CO(2) and/or N fertilization treatment for several years. Our results provide evidence that the richness and composition of the cellulolytic fungi surveyed in this study were distinct in the DNA- and cDNA-based gene surveys and were dominated by Basidiomycota that have low or no representation in public databases. The surveys did not detect differences in richness or phylum-level composition of cbhI-containing, cellulolytic fungi that correlated with elevated CO(2) or N fertilization at the time of sampling. PMID:22467503

  15. Carbon emissions from forest conversion by Kalimantan oil palm plantations

    NASA Astrophysics Data System (ADS)

    Carlson, Kimberly M.; Curran, Lisa M.; Asner, Gregory P.; Pittman, Alice Mcdonald; Trigg, Simon N.; Marion Adeney, J.

    2013-03-01

    Oil palm supplies >30% of world vegetable oil production. Plantation expansion is occurring throughout the tropics, predominantly in Indonesia, where forests with heterogeneous carbon stocks undergo high conversion rates. Quantifying oil palm's contribution to global carbon budgets therefore requires refined spatio-temporal assessments of land cover converted to plantations. Here, we report oil palm development across Kalimantan (538,346km2) from 1990 to 2010, and project expansion to 2020 within government-allocated leases. Using Landsat satellite analyses to discern multiple land covers, coupled with above- and below-ground carbon accounting, we develop the first high-resolution carbon flux estimates from Kalimantan plantations. From 1990 to 2010, 90% of lands converted to oil palm were forested (47% intact, 22% logged, 21% agroforests). By 2010, 87% of total oil palm area (31,640km2) occurred on mineral soils, and these plantations contributed 61-73% of 1990-2010 net oil palm emissions (0.020-0.024GtCyr-1). Although oil palm expanded 278% from 2000 to 2010, 79% of allocated leases remained undeveloped. By 2020, full lease development would convert 93,844km2 (~ 90% forested lands, including 41% intact forests). Oil palm would then occupy 34% of lowlands outside protected areas. Plantation expansion in Kalimantan alone is projected to contribute 18-22% (0.12-0.15GtCyr-1) of Indonesia's 2020 CO2-equivalent emissions. Allocated oil palm leases represent a critical yet undocumented source of deforestation and carbon emissions.

  16. Decoupling the Influence of Leaf and Root Hydraulic Conductances on Stomatal Conductance and its Sensitivity to Vapor Pressure Deficit as Soil Dries in a Drained Loblolly Pine Plantation

    NASA Astrophysics Data System (ADS)

    Domec, J.; Noormets, A.; King, J. S.; McNulty, S. G.; Sun, G.; Gavazzi, M. J.; Boggs, J. L.

    2008-12-01

    The conversion of wetlands to intensively managed forest lands in eastern North Carolina is widespread and the consequences on plant hydraulic properties and water balances are not well studied. Precipitation and soil moisture in North America will be modified in the future and forest trees in the US will be challenged by warmer temperature, higher leaf-to-air water vapor pressure deficit (D), and more frequent summer droughts. Many studies have examined the relationships between whole tree hydraulic conductance (Ktree) and stomatal conductance (gs), but Ktree remains an ill-defined quantity because it depends on a series of resistances, mainly controlled by the conductance in roots (Kroot) and leaves (Kleaf). To explain the variation in Ktree, we characterized Kroot and Kleaf and how they responded to environmental drivers such as soil moisture availability and D. In addition, the role of dynamic variations in Kroot and Kleaf in mediating stomatal control of transpiration and its response to D was studied. The 2007 summer drought was used as a means to challenge the hydraulic system, allowing testing how broadly predictions about its behaviour hold outside the range of typical conditions. Roots and leaves were the weakest points in the whole tree hydraulic system, and contributed for more than 75% of the total tree hydraulic resistance. Effects of drought on Ktree altered the partitioning of the resistance between roots and leaves and as soil moisture declined below 50% relative extractable water (REW), Kroot declined faster than Kleaf and became the dominant hydraulic fuse regulating Ktree. Although Ktree depended on soil moisture, its dynamics was tempered by current-year needle elongation that increased significantly Kleaf during the dry months when REW was below 50%. To maintain the integrity of the xylem hydraulic continuum from roots to leaves, stomata were highly responsive in coordinating transpiration with dynamic variation in Ktree. Daily maximum gs and

  17. Different Water Use Strategies of Juvenile and Adult Caragana intermedia Plantations in the Gonghe Basin, Tibet Plateau

    PubMed Central

    Jia, Zhiqing; Zhu, Yajuan; Liu, Liying

    2012-01-01

    Background In a semi-arid ecosystem, water is one of the most important factors that affect vegetation dynamics, such as shrub plantation. A water use strategy, including the main water source that a plant species utilizes and water use efficiency (WUE), plays an important role in plant survival and growth. The water use strategy of a shrub is one of the key factors in the evaluation of stability and sustainability of a plantation. Methodology/Principal Findings Caragana intermedia is a dominant shrub of sand-binding plantations on sand dunes in the Gonghe Basin in northeastern Tibet Plateau. Understanding the water use strategy of a shrub plantation can be used to evaluate its sustainability and long-term stability. We hypothesized that C. intermedia uses mainly deep soil water and its WUE increases with plantation age. Stable isotopes of hydrogen and oxygen were used to determine the main water source and leaf carbon isotope discrimination was used to estimate long-term WUE. The root system was investigated to determine the depth of the main distribution. The results showed that a 5-year-old C. intermedia plantation used soil water mainly at a depth of 0–30 cm, which was coincident with the distribution of its fine roots. However, 9- or 25-year-old C. intermedia plantations used mainly 0–50 cm soil depth water and the fine root system was distributed primarily at soil depths of 0–50 cm and 0–60 cm, respectively. These sources of soil water are recharged directly by rainfall. Moreover, the long-term WUE of adult plantations was greater than that of juvenile plantations. Conclusions The C. intermedia plantation can change its water use strategy over time as an adaptation to a semi-arid environment, including increasing the depth of soil water used for root growth, and increasing long-term WUE. PMID:23029303

  18. The effects of nitrogen fertilization on N2O emissions from a rubber plantation

    PubMed Central

    Zhou, Wen-Jun; Ji, Hong-li; Zhu, Jing; Zhang, Yi-Ping; Sha, Li-Qing; Liu, Yun-Tong; Zhang, Xiang; Zhao, Wei; Dong, Yu-xin; Bai, Xiao-Long; Lin, You-Xin; Zhang, Jun-Hui; Zheng, Xun-Hua

    2016-01-01

    To gain the effects of N fertilizer applications on N2O emissions and local climate change in fertilized rubber (Hevea brasiliensis) plantations in the tropics, we measured N2O fluxes from fertilized (75 kg N ha−1 yr−1) and unfertilized rubber plantations at Xishuangbanna in southwest China over a 2-year period. The N2O emissions from the fertilized and unfertilized plots were 4.0 and 2.5 kg N ha−1 yr−1, respectively, and the N2O emission factor was 1.96%. Soil moisture, soil temperature, and the area weighted mean ammoniacal nitrogen (NH4+-N) content controlled the variations in N2O flux from the fertilized and unfertilized rubber plantations. NH4+-N did not influence temporal changes in N2O emissions from the trench, slope, or terrace plots, but controlled spatial variations in N2O emissions among the treatments. On a unit area basis, the 100-year carbon dioxide equivalence of the fertilized rubber plantation N2O offsets 5.8% and 31.5% of carbon sink of the rubber plantation and local tropical rainforest, respectively. When entire land area in Xishuangbanna is considered, N2O emissions from fertilized rubber plantations offset 17.1% of the tropical rainforest’s carbon sink. The results show that if tropical rainforests are converted to fertilized rubber plantations, regional N2O emissions may enhance local climate warming. PMID:27324813

  19. The effects of nitrogen fertilization on N2O emissions from a rubber plantation

    NASA Astrophysics Data System (ADS)

    Zhou, Wen-Jun; Ji, Hong-Li; Zhu, Jing; Zhang, Yi-Ping; Sha, Li-Qing; Liu, Yun-Tong; Zhang, Xiang; Zhao, Wei; Dong, Yu-Xin; Bai, Xiao-Long; Lin, You-Xin; Zhang, Jun-Hui; Zheng, Xun-Hua

    2016-06-01

    To gain the effects of N fertilizer applications on N2O emissions and local climate change in fertilized rubber (Hevea brasiliensis) plantations in the tropics, we measured N2O fluxes from fertilized (75 kg N ha‑1 yr‑1) and unfertilized rubber plantations at Xishuangbanna in southwest China over a 2-year period. The N2O emissions from the fertilized and unfertilized plots were 4.0 and 2.5 kg N ha‑1 yr‑1, respectively, and the N2O emission factor was 1.96%. Soil moisture, soil temperature, and the area weighted mean ammoniacal nitrogen (NH4+-N) content controlled the variations in N2O flux from the fertilized and unfertilized rubber plantations. NH4+-N did not influence temporal changes in N2O emissions from the trench, slope, or terrace plots, but controlled spatial variations in N2O emissions among the treatments. On a unit area basis, the 100-year carbon dioxide equivalence of the fertilized rubber plantation N2O offsets 5.8% and 31.5% of carbon sink of the rubber plantation and local tropical rainforest, respectively. When entire land area in Xishuangbanna is considered, N2O emissions from fertilized rubber plantations offset 17.1% of the tropical rainforest’s carbon sink. The results show that if tropical rainforests are converted to fertilized rubber plantations, regional N2O emissions may enhance local climate warming.

  20. The effects of nitrogen fertilization on N2O emissions from a rubber plantation.

    PubMed

    Zhou, Wen-Jun; Ji, Hong-Li; Zhu, Jing; Zhang, Yi-Ping; Sha, Li-Qing; Liu, Yun-Tong; Zhang, Xiang; Zhao, Wei; Dong, Yu-Xin; Bai, Xiao-Long; Lin, You-Xin; Zhang, Jun-Hui; Zheng, Xun-Hua

    2016-01-01

    To gain the effects of N fertilizer applications on N2O emissions and local climate change in fertilized rubber (Hevea brasiliensis) plantations in the tropics, we measured N2O fluxes from fertilized (75 kg N ha(-1) yr(-1)) and unfertilized rubber plantations at Xishuangbanna in southwest China over a 2-year period. The N2O emissions from the fertilized and unfertilized plots were 4.0 and 2.5 kg N ha(-1) yr(-1), respectively, and the N2O emission factor was 1.96%. Soil moisture, soil temperature, and the area weighted mean ammoniacal nitrogen (NH4(+)-N) content controlled the variations in N2O flux from the fertilized and unfertilized rubber plantations. NH4(+)-N did not influence temporal changes in N2O emissions from the trench, slope, or terrace plots, but controlled spatial variations in N2O emissions among the treatments. On a unit area basis, the 100-year carbon dioxide equivalence of the fertilized rubber plantation N2O offsets 5.8% and 31.5% of carbon sink of the rubber plantation and local tropical rainforest, respectively. When entire land area in Xishuangbanna is considered, N2O emissions from fertilized rubber plantations offset 17.1% of the tropical rainforest's carbon sink. The results show that if tropical rainforests are converted to fertilized rubber plantations, regional N2O emissions may enhance local climate warming. PMID:27324813

  1. [Phase-directional management of protective plantations. I. Fundamentals].

    PubMed

    Jiang, Fengqi; Zhu, Jiaojun

    2002-10-01

    In order to ensure the higher effectiveness, more stability and sustainability of Protective plantations, the definition of phase-directional management (PDM) of protective plantations was brought forward on the basis of management researches and practices for protective plantations. The basics of PDM is protective maturity, which is defined as the time when the protective plantations attain to the state that the protective plantations can provide effective and complete protection to the objects needed to be protected. Protective maturity has two points, initial protective maturity age (IPMA), the age of protective maturity started, and terminal protective maturity age (TPMA), the age of protective maturity ended. Three management phases of protective plantation, i.e., prematurity phase, the period from sapling or establishment to initial protective maturity, protective maturity phase, the period of protective maturity lasting, and regeneration phase, the period during regeneration and before the establishment, are divided based on the fundamental of protective maturity. Directional management of protective plantation means that all of the management techniques in each phase are directed at the aim of protective maturity, i.e., protective maturity is the direction of management of protective forests, and protective maturity is the final objective for the management of protective forests. In order to sustain the protective maturity state, corresponding measures should be conducted in each phase, according to the classification of protective plantations. In pre-maturity phase, the purpose of managing is to accelerate the protective maturity, therefore, the measures such as weed clearing, soil cultivation, irrigation, fertilization, intercropping and branch cutting etc. should be conducted in protective plantations. In maturity phase, the aim of managing is to sustain the protective maturity, i.e., the techniques (tending and thinning) of controlling the structure of

  2. Nitrogen Deposition Enhances Carbon Sequestration by Plantations in Northern China

    PubMed Central

    Du, Zhihong; Wang, Wei; Zeng, Wenjing; Zeng, Hui

    2014-01-01

    Nitrogen (N) deposition and its ecological effects on forest ecosystems have received global attention. Plantations play an important role in mitigating climate change through assimilating atmospheric CO2. However, the mechanisms by which increasing N additions affect net ecosystem production (NEP) of plantations remain poorly understood. A field experiment was initialized in May 2009, which incorporated additions of four rates of N (control (no N addition), low-N (5 g N m−2 yr−1), medium-N (10 g N m−2 yr−1), and high-N (15 g N m−2 yr−1)) at the Saihanba Forestry Center, Hebei Province, northern China, a locality that contains the largest area of plantations in China. Net primary production (NPP), soil respiration, and its autotrophic and heterotrophic components were measured. Plant tissue carbon (C) and N concentrations (including foliage, litter, and fine roots), microbial biomass, microbial community composition, extracellular enzyme activities, and soil pH were also measured. N addition significantly increased NPP, which was associated with increased litter N concentrations. Autotrophic respiration (AR) increased but heterotrophic respiration (HR) decreased in the high N compared with the medium N plots, although the HR in high and medium N plots did not significantly differ from that in the control. The increased AR may derive from mycorrhizal respiration and rhizospheric microbial respiration, not live root respiration, because fine root biomass and N concentrations showed no significant differences. Although the HR was significantly suppressed in the high-N plots, soil microbial biomass, composition, or activity of extracellular enzymes were not significantly changed. Reduced pH with fertilization also could not explain the pattern of HR. The reduction of HR may be related to altered microbial C use efficiency. NEP was significantly enhanced by N addition, from 149 to 426.6 g C m−2 yr−1. Short-term N addition may significantly enhance the

  3. Persistence and detection of black truffle ectomycorrhizas in plantations: comparison between two field detection methods.

    PubMed

    Sánchez, Sergio; Ágreda, Teresa; Águeda, Beatriz; Martín, María; de Miguel, Ana María; Barriuso, Juan

    2014-04-01

    Owners of black truffle (Tuber melanosporum) plantations are concerned about the persistence of its mycorrhizas and mycelium in the soil, especially until the appearance of the "truffle burn" areas and the triggering of sporocarp production, at least 5-7 years after planting truffle-inoculated seedlings. During this period, the farmer does not know whether his management is promoting black truffle development. To study the presence and abundance of T. melanosporum ectomycorrhizas in plantations, two sampling methods, direct sampling of root tips and soil core collection, are compared by analyzing 48 evergreen oak trees (Quercus ilex) inoculated with truffle. Those trees are grouped by age (<6, 6-9, >9 years old) and presence or absence of truffle production. T. melanosporum was present in 46 out of the 48 studied trees, and its ectomycorrhizas appeared in 65% of the ectomycorrhizal tips. Its abundance is significantly higher with productive trees and young trees. Direct sampling of root tips and soil core collection were equally effective in detecting this species, although soil core collection proved a better method to also evaluate ectomycorrhizal fungal diversity. To detect the presence of T. melanosporum in a given plantation, three samples suffice, with a single sample per random tree. Although the presence of mycorrhizas is not a sure sign of the future success of a black truffle plantation, its absence influences managers as to whether to continue culturing truffles in a plantation. PMID:24509698

  4. A water use and growth model for Eucalyptus plantation in water-limited conditions

    SciTech Connect

    Calder, I.R.

    1992-12-31

    To investigate the environmental impact of plantation forestry using fast-growing tree species in southern India, a program of field studies was initiated in 1987 specifically to measure the water use, nutrient uptake and growth rates of the plantations. A water use and growth (WAG) model is proposed for calculating transpiration and growth of Eucalyptus plantation in water-limited conditions. The model is based on the measured relationships between transpiration rate and basal cross-sectional area and soil moisture availability. The volume growth rate (in water-limited conditions) is assumed to be proportional to the volume of water transpired. The model is calibrated using (deuterium tracing) measurements of transpiration and measurements of growth recorded at the Puradal experimental plantation, Karnataka, southern India.

  5. Biomass Accumulation and Carbon Sequestration in Four Different Aged Casuarina equisetifolia Coastal Shelterbelt Plantations in South China

    PubMed Central

    Zou, Bi; Guo, Zhihua; Li, Zhian; Zhu, Weixing

    2013-01-01

    Thousands of kilometers of shelterbelt plantations of Casuarina equisetifolia have been planted to protect the southeast coastline of China. These plantations also play an important role in the regional carbon (C) cycling. In this study, we examined plant biomass increment and C accumulation in four different aged C. equisetifolia plantations in sandy beaches in South China. The C accumulated in the C. equisetifolia plant biomass increased markedly with stand age. The annual rate of C accumulation in the C. equisetifolia plant biomass during 0–3, 3–6, 6–13 and 13–18 years stage was 2.9, 8.2, 4.2 and 1.0 Mg C ha−1 yr−1, respectively. Soil organic C (SOC) at the top 1 m soil layer in these plantations was 17.74, 5.14, 6.93, and 11.87 Mg C ha−1, respectively, with SOC density decreasing with increasing soil depth. Total C storage in the plantation ecosystem averaged 26.57, 38.50, 69.78, and 79.79 Mg C ha−1 in the 3, 6, 13 and 18- yrs plantation, with most of the C accumulated in the aboveground biomass rather than in the belowground root biomass and soil organic C. Though our results suggest that C. equisetifolia plantations have the characteristics of fast growth, high biomass accumulation, and the potential of high C sequestration despite planting in poor soil conditions, the interactive effects of soil condition, natural disturbance, and human policies on the ecosystem health of the plantation need to be further studied to fully realize the ecological and social benefits of the C equisetifolia shelterbelt forests in South China. PMID:24143236

  6. [Soil physical and chemical characteristics under different vegetation restoration patterns in China south subtropical area].

    PubMed

    Kang, Bing; Liu, Shi-rong; Cai, Dao-xiong; Lu, Li-hua; He, Ri-ming; Gao, Yan-xia; Di, Wei-zhi

    2010-10-01

    This paper studied the change of soil physical and chemical properties under eleven vegetation restoration patterns (1 kind of secondary forest, 2 kinds of pure coniferous plantations, 5 kinds of evergreen broad-leaved plantations, 2 kinds of conifer and broad-leaved mixed plantations, and 1 kind of shrub) typical in Daqingshan of Guangxi. Obvious differences were observed in the soil physical and chemical properties under different vegetation restoration patterns. The soil physical properties were better in secondary forest but poorer in pure conifer plantations. Conifer and broad-leaved mixed plantations had lower soil bulk density, and their soil total porosity and water-holding capacity were higher than those in pure plantations. There were no significant differences in the soil porosity among the 5 evergreen broad-leaved plantations. Except that of soil total K, the contents of soil nutrients in secondary forest were higher than those in plantations, and the soil C/N ratio and pH value were relatively lower. Comparing with shrub, the 9 plantations had an obvious change in their soil nutrient contents, e. g. , the increase of soil total N and available K. The 2 pure coniferous plantations had lower soil nutrient contents, but after mixed planted with evergreen broad-leaved trees, their soil nutrient contents increased markedly, and the soil C/N ratio decreased. PMID:21328932

  7. Nitrogen-Fixing Bacteria in Eucalyptus globulus Plantations

    PubMed Central

    da Silva, Marliane de Cássia Soares; Paula, Thiago de Almeida; Moreira, Bruno Coutinho; Carolino, Manuela; Cruz, Cristina; Bazzolli, Denise Mara Soares; Silva, Cynthia Canedo; Kasuya, Maria Catarina Megumi

    2014-01-01

    Eucalypt cultivation is an important economic activity worldwide. In Portugal, Eucalyptus globulus plantations account for one-third of the total forested area. The nutritional requirements of this crop have been well studied, and nitrogen (N) is one of the most important elements required for vegetal growth. N dynamics in soils are influenced by microorganisms, such as diazotrophic bacteria (DB) that are responsible for biological nitrogen fixation (BNF), so the aim of this study was to evaluate and identity the main groups of DB in E. globulus plantations. Samples of soil and root systems were collected in winter and summer from three different Portuguese regions (Penafiel, Gavião and Odemira). We observed that DB communities were affected by season, N fertilization and moisture. Furthermore Bradyrhizobium and Burkholderia were the most prevalent genera in these three regions. This is the first study describing the dynamic of these bacteria in E. globulus plantations, and these data will likely contribute to a better understanding of the nutritional requirements of eucalypt cultivation and associated organic matter turnover. PMID:25340502

  8. Age and thinning effects on the temperature sensitivities of respiration in loblolly pine plantations in eastern North Carolina

    NASA Astrophysics Data System (ADS)

    Miao, G.; Noormets, A.

    2014-12-01

    Age and silvicultural interventions are two important factors to characterize the development of commercial plantations. Effects of the two factors are of importance in quantifying the carbon dynamics in these artificial systems, but remain unclear. From 9 years (2005-2013) of carbon exchange observations in a mature (13 years old in 2005) and a young (2 years old in 2005) loblolly pine plantations located on the lower coastal plain in eastern North Carolina, we investigated the difference in temperature sensitivities (Q10) of ecosystem respiration (ER) of the two plantations of different ages. The mature plantation was thinned in August 2009, therefore, we compared the ER before and after thinning to estimate the potential response of Q10 to thinning in the mature plantation. Before thinning (years of 2005 - early half year of 2009), Q10 of ER in the mature plantation was similar across years. Even during a severe drought (e.g. 2007), Q10 did not differ from other years (p = 0.2 - 0.8 between years). The mean Q10 before harvesting was 2.33±0.05 (mean±SE). After thinning (years of 2010-2013), there was significant inter-annual variation in Q10 with an overall estimate at 2.23±0.05. The young plantation also exhibited significant inter-annual variations in Q10, and the overall Q10 was 2.99±0.11, higher than that of the mature plantation. The increased variability of temperature sensitivity after thinning in the mature plantation might be associated with the altered physical environment by thinning such as soil bulk density and soil water content, whereas the similar pattern in the young plantation might result from the primary contribution of heterotrophic respiration and also be confounded with the fast growth of young seedlings.

  9. Restoration of mangrove plantations and colonisation by native species in Leizhou bay, South China

    USGS Publications Warehouse

    Ren, H.; Jian, S.; Lu, H.; Zhang, Q.; Shen, W.; Han, W.; Yin, Z.; Guo, Q.

    2008-01-01

    To examine the natural colonisation of native mangrove species into remediated exotic mangrove stands in Leizhou Bay, South China, we compared soil physical-chemical properties, community structure and recruitments of barren mangrove areas, native mangrove species plantations, and exotic mangrove species-Sonneratia apetala Buch.Ham-between plantations and natural forest. We found that severely degraded mangrove stands could not regenerate naturally without human intervention due to severely altered local environments, whereas some native species had been recruited into the 4-10 year S. apetala plantations. In the first 10 years, the exotic species S. apetala grew better than native species such as Rhizophora stylosa Griff and Kandelia candel (Linn.) Druce. The mangrove plantation gradually affected soil physical and chemical properties during its recovery. The exotic S. apetala was more competitive than native species and its plantation was able to restore soil organic matter in about 14 years. Thus, S. apetala can be considered as a pioneer species to improve degraded habitats to facilitate recolonisation by native mangrove species. However, removal to control proliferation may be needed at late stages to facilitate growth of native species. To ensure sustainability of mangroves in South China, the existing mangrove wetlands must be managed as an ecosystem, with long-term scientific monitoring program in place. ?? 2007 The Ecological Society of Japan.

  10. Tree Plantation Systems Influence Nitrogen Retention and the Abundance of Nitrogen Functional Genes in the Solomon Islands

    PubMed Central

    Reverchon, Frédérique; Bai, Shahla H.; Liu, Xian; Blumfield, Timothy J.

    2015-01-01

    Tree mono-plantations are susceptible to soil nutrient impoverishment and mixed species plantations have been proposed as a way of maintaining soil fertility while enhancing biodiversity. In the Solomon Islands, mixed species plantations where teak (Tectona grandis) is inter-planted with a local tree species (Flueggea flexuosa) have been used as an alternative to teak mono-plantations and are expected to increase soil microbial diversity and modify microbial biogeochemical processes. In this study, we quantified the abundance of microbial functional genes involved in the nitrogen (N) cycle from soil samples collected in teak, flueggea, and mixed species plantations. Furthermore, we measured soil properties such as pH, total carbon (C) and total N, stable N isotope composition (δ15N), and inorganic N pools. Soil pH and δ15N were higher under teak than under flueggea, which indicates that intercropping teak with flueggea may decrease bacterial activities and potential N losses. Higher C:N ratios were found under mixed species plantations than those under teak, suggesting an enhancement of N immobilization that would help preventing fast N losses. However, inorganic N pools remained unaffected by plant cover. Inter-planting teak with flueggea in mixed species plantations generally increased the relative abundance of denitrification genes and promoted the enrichment of nosZ-harboring denitrifiers. However, it reduced the abundance of bacterial amoA (ammonia monooxygenase) genes compared to teak mono-plantations. The abundance of most denitrification genes correlated with soil total N and C:N ratio, while bacterial and archeal nitrification genes correlated positively with soil NH4+ concentrations. Altogether, these results show that the abundance of bacterial N-cycling functional guilds vary under teak and under mixed species plantations, and that inter-planting teak with flueggea may potentially alleviate N losses associated with nitrification and denitrification

  11. Tree Plantation Systems Influence Nitrogen Retention and the Abundance of Nitrogen Functional Genes in the Solomon Islands.

    PubMed

    Reverchon, Frédérique; Bai, Shahla H; Liu, Xian; Blumfield, Timothy J

    2015-01-01

    Tree mono-plantations are susceptible to soil nutrient impoverishment and mixed species plantations have been proposed as a way of maintaining soil fertility while enhancing biodiversity. In the Solomon Islands, mixed species plantations where teak (Tectona grandis) is inter-planted with a local tree species (Flueggea flexuosa) have been used as an alternative to teak mono-plantations and are expected to increase soil microbial diversity and modify microbial biogeochemical processes. In this study, we quantified the abundance of microbial functional genes involved in the nitrogen (N) cycle from soil samples collected in teak, flueggea, and mixed species plantations. Furthermore, we measured soil properties such as pH, total carbon (C) and total N, stable N isotope composition (δ(15)N), and inorganic N pools. Soil pH and δ(15)N were higher under teak than under flueggea, which indicates that intercropping teak with flueggea may decrease bacterial activities and potential N losses. Higher C:N ratios were found under mixed species plantations than those under teak, suggesting an enhancement of N immobilization that would help preventing fast N losses. However, inorganic N pools remained unaffected by plant cover. Inter-planting teak with flueggea in mixed species plantations generally increased the relative abundance of denitrification genes and promoted the enrichment of nosZ-harboring denitrifiers. However, it reduced the abundance of bacterial amoA (ammonia monooxygenase) genes compared to teak mono-plantations. The abundance of most denitrification genes correlated with soil total N and C:N ratio, while bacterial and archeal nitrification genes correlated positively with soil NH4 (+) concentrations. Altogether, these results show that the abundance of bacterial N-cycling functional guilds vary under teak and under mixed species plantations, and that inter-planting teak with flueggea may potentially alleviate N losses associated with nitrification and

  12. Above- and Below-Ground Carbon Stocks in an Indigenous Tree (Mytilaria laosensis) Plantation Chronosequence in Subtropical China

    PubMed Central

    Zhao, Jinlong; Tao, Yi

    2014-01-01

    More than 60% of the total area of tree plantations in China is in subtropical, and over 70% of subtropical plantations consist of pure stands of coniferous species. Because of the poor ecosystem services provided by pure coniferous plantations and the ecological instability of these stands, a movement is under way to promote indigenous broadleaf plantation cultivation as a promising alternative. However, little is known about the carbon (C) stocks in indigenous broadleaf plantations and their dependence on stand age. Thus, we studied above- and below-ground biomass and C stocks in a chronosequence of Mytilaria laosensis plantations in subtropical China; stands were 7, 10, 18, 23, 29 and 33 years old. Our assessments included tree, shrub, herb and litter layers. We used plot-level inventories and destructive tree sampling to determine vegetation C stocks. We also measured soil C stocks by analyses of soil profiles to 100 cm depth. C stocks in the tree layer dominated the above-ground ecosystem C pool across the chronosequence. C stocks increased with age from 7 to 29 years and plateaued thereafter due to a reduction in tree growth rates. Minor C stocks were found in the shrub and herb layers of all six plantations and their temporal fluctuations were relatively small. C stocks in the litter and soil layers increased with stand age. Total above-ground ecosystem C also increased with stand age. Most increases in C stocks in below-ground and total ecosystems were attributable to increases in soil C content and tree biomass. Therefore, considerations of C sequestration potential in indigenous broadleaf plantations must take stand age into account. PMID:25343446

  13. Seasonal abundance and activity of pill millipedes ( Arthrosphaera magna) in mixed plantation and semi-evergreen forest of southern India

    NASA Astrophysics Data System (ADS)

    Ashwini, Krishna M.; Sridhar, Kandikere R.

    2006-01-01

    Seasonal occurrence and activity of endemic pill millipedes ( Arthrosphaera magna) were examined in organically managed mixed plantation and semi-evergreen forest reserve in southwest India between November 1996 and September 1998. Abundance and biomass of millipedes were highest in both habitats during monsoon season. Soil moisture, conductivity, organic carbon, phosphate, potassium, calcium and magnesium were higher in plantation than in forest. Millipede abundance and biomass were about 12 and 7 times higher in plantation than in forest, respectively ( P < 0.001). Their biomass increased during post-monsoon, summer and monsoon in the plantation ( P < 0.001), but not in forest ( P > 0.05). Millipede abundance and biomass were positively correlated with rainfall ( P = 0.01). Besides rainfall, millipedes in plantation were positively correlated with soil moisture as well as temperature ( P = 0.001). Among the associated fauna with pill millipedes, earthworms rank first followed by soil bugs in both habitats. Since pill millipedes are sensitive to narrow ecological changes, the organic farming strategies followed in mixed plantation and commonly practiced in South India seem not deleterious for the endangered pill millipedes Arthrosphaera and reduce the risk of local extinctions.

  14. Evapotranspiration components determined by eddy covariance and sap flux measurements in oil palm plantations in Sumatra, Indonesia

    NASA Astrophysics Data System (ADS)

    Meijide, Ana; Röll, Alexander; Niu, Furong; June, Tania; Hölscher, Dirk; Knohl, Alexander

    2015-04-01

    The expansion of oil palm cultivation fueled by the increasing global demand for palm oil is leading to massive land transformations in tropical areas, particularly in South-East Asia. Conversions of forest land to oil palm plantations likely affect ecosystem water fluxes. However, there is a lack of information on water fluxes from oil palm plantations as well as on the partitioning of these fluxes into its different components such as transpiration and evaporation. It is expected that water fluxes from oil palm plantations vary temporally, both long-term, i.e. between different age-classes of plantations, and short-term, i.e. from day to day within a certain plantation (e.g. during or after periods of rainfall). A proper evaluation of water fluxes from oil palm plantations thus requires an experimental design encompassing these types of variability. To assess evapotranspiration (ET) rates, an eddy covariance tower was installed in a 2-year-old oil palm plantation in the lowlands of Jambi, Sumatra; it was subsequently moved to a 12-year-old oil palm plantation located in the same region. In parallel to the ET, sap flux density was measured on 16 leaf petioles on four oil palms; stand transpiration rates were derived from these measurements with stand inventory data. The parallel measurements ran for several weeks in both plantations. Preliminary results for our period of study show that the average ET rate of the 2-year-old oil palm plantation was 5.2 mm day-1; values up to 7.0 mm day-1 were observed on dry, sunny days with non-limiting soil moisture. Stand transpiration (T) by the young oil palms was very low, 0.3 mm day-1on average, and only showed a small variation between days. Under optimal environmental conditions, the ratio of T to total ET was up to 0.08 in the young plantation, while in the mature, 12-year-old plantation, it was significantly higher and reached 0.5. Transpiration rates in the mature oil palm plantation were about six- to seven-fold higher

  15. Responses of nitrous oxide emissions to nitrogen and phosphorus additions in two tropical plantations with N-fixing vs. non-N-fixing tree species

    NASA Astrophysics Data System (ADS)

    Zhang, W.; Zhu, X.; Luo, Y.; Rafique, R.; Chen, H.; Huang, J.; Mo, J.

    2014-01-01

    Leguminous tree plantations at phosphorus (P) limited sites may result in higher rates of nitrous oxide (N2O) emissions, however, the effects of nitrogen (N) and P applications on soil N2O emissions from plantations with N-fixing vs. non-N-fixing tree species has rarely been studied in the field. We conducted an experimental manipulation of N and P additions in two tropical plantations with Acacia auriculiformis (AA) and Eucalyptus urophylla (EU) tree species in South China. The objective was to determine the effects of N- or P-addition alone, as well as NP application together on soil N2O emissions from tropical plantations with N-fixing vs. non-N-fixing tree species. We found that the average N2O emission from control was greater in AA (2.26 ± 0.06 kg N2O-N ha-1 yr-1) than in EU plantation (1.87 ± 0.05 kg N2O-N ha-1 yr-1). For the AA plantation, N-addition stimulated the N2O emission from soil while P-addition did not. Applications of N with P together significantly decreased N2O emission compared to N-addition alone, especially in high level treatment plots (decreased by 18%). In the EU plantation, N2O emissions significantly decreased in P-addition plots compared with the controls, however, N- and NP-additions did not. The differing response of N2O emissions to N- or P-addition was attributed to the higher initial soil N status in the AA than that of the EU plantation, due to symbiotic N fixation in the former. Our results suggest that atmospheric N deposition potentially stimulates N2O emissions from leguminous tree plantations in the tropics, whereas P fertilization has the potential to mitigate N deposition-induced N2O emissions from such plantations.

  16. Responses of nitrous oxide emissions to nitrogen and phosphorus additions in two tropical plantations with N-fixing vs. non-N-fixing tree species

    NASA Astrophysics Data System (ADS)

    Zhang, W.; Zhu, X.; Luo, Y.; Rafique, R.; Chen, H.; Huang, J.; Mo, J.

    2014-09-01

    Leguminous tree plantations at phosphorus (P) limited sites may result in excess nitrogen (N) and higher rates of nitrous oxide (N2O) emissions. However, the effects of N and P applications on soil N2O emissions from plantations with N-fixing vs. non-N-fixing tree species have rarely been studied in the field. We conducted an experimental manipulation of N and/or P additions in two plantations with Acacia auriculiformis (AA, N-fixing) and Eucalyptus urophylla (EU, non-N-fixing) in South China. The objective was to determine the effects of N or P addition alone, as well as NP application together on soil N2O emissions from these tropical plantations. We found that the average N2O emission from control was greater in the AA (2.3 ± 0.1 kg N2O-N ha-1 yr-1) than in EU plantation (1.9 ± 0.1 kg N2O-N ha-1 yr-1). For the AA plantation, N addition stimulated N2O emission from the soil while P addition did not. Applications of N with P together significantly decreased N2O emission compared to N addition alone, especially in the high-level treatments (decreased by 18%). In the EU plantation, N2O emissions significantly decreased in P-addition plots compared with the controls; however, N and NP additions did not. The different response of N2O emission to N or P addition was attributed to the higher initial soil N status in the AA than that of EU plantation, due to symbiotic N fixation in the former. Our result suggests that atmospheric N deposition potentially stimulates N2O emissions from leguminous tree plantations in the tropics, whereas P fertilization has the potential to mitigate N-deposition-induced N2O emissions from such plantations.

  17. CO2 and CH4 fluxes from oil palm plantations in Sumatra, Indonesia: effects of palm age and environmental conditions

    NASA Astrophysics Data System (ADS)

    Meijide, A.; Hassler, E.; Corre, M. D.; June, T.; Sabajo, C.; Veldkamp, E.; Knohl, A.

    2015-12-01

    Global increasing demand of palm oil is leading to the expansion of oil palm plantations, particularly in SE Asia, which in Sumatran lowlands has resulted in a 21% forest area loss. Large photosynthesis rates are expected for oil palms, due to their high growth and yield production. However, there is very limited information on their effect on carbon dioxide (CO2) fluxes and their sink or source strength at ecosystem scale. For methane (CH4) fluxes, research has mainly focused in oil palm plantations located on peatlands, but no information is available at ecosystem level from plantations on mineral soils. With the aim of studying CO2 fluxes during the non-productive and productive phases of oil palm cultivation, an eddy covariance (EC) tower was installed in a 2 year old oil palm plantation, where it was measuring for 8 months, and was subsequently moved to a 12 year old plantation, both in the province of Jambi, Sumatra. The EC system consisted of a Licor 7500A and an ultrasonic Metek anemometer, operating at 10 Hz, installed on a 7m and 22m tower respectively. In the 12 year old plantation, the tower was also equipped with a Los Gatos FGGA-24EP, to assess CH4 fluxes. Chamber measurements were also carried out to obtain information on respiration and CH4 fluxes from the soil. Radiation was the major driver controlling net carbon uptake, while soil moisture did not play a significant role. Average net ecosystem exchange in the hours of the day with higher radiation for the whole measurement period was 10 μmol m-2 s-1 for the 2 year old plantation and -22 μmol m-2 s-1 in the 12 year old. The analysis of the cumulative fluxes show that the non-productive plantation was a carbon source of around 636 g CO2 m-2 during the 8 months of measurements, while in the productive period, it acted as a strong carbon sink (-794 g CO2 m-2 yr-1). Methane uptake was observed in the soil in both plantations and also for the whole ecosystem in the 12 year old one, but its

  18. Modeling Pine Plantation NEP Using Landsat

    NASA Astrophysics Data System (ADS)

    Wynne, R. H.; Potter, C. S.; Blinn, C. E.

    2008-12-01

    The CASA (Carnegie Ames Stanford Approach) ecosystem process model predicts terrestrial ecosystem fluxes using satellite-based inputs at a maximum geographic resolution of 30 meters to infer variability in forest carbon fluxes. We are using CASA to model pine plantation net ecosystem production (NEP) under a range of standard silvicultural prescriptions, primarily thinning by fertilization interactions. Landsat scenes from WRS path/row 14/35, 21/37, and 16/34 are being used. Within each frame, all available cloud-free scenes within a two- to three-year period have been obtained from the USGS EROS Data Center processed to L1T, and subsequently converted to top-of-atmosphere reflectance using standard methods and the latest calibration parameter files. Atmospheric amelioration started with dark object subtraction (band minimum) and only proceeded to more complex techniques as necessary. Subsequent to preprocessing, the reduced simple ratio (RSR; using global min/max) was calculated for all images for each WRS path/row. Pure pine pixels in each frame were identified using unsupervised classification of the most recent leaf-off scene. We developed four age classes using two decades of Landsat data over each WRS path/row. CASA runs, which require soil parameters, and gridded climate/solar radiation in addition to satellite-derived vegetation indices, are now complete. Soil respiration and productivity estimates are being evaluated using a regionwide network of validation sites spanning the range of loblolly pine (Texas to Virginia). Preliminary results indicate that Landsat-based process modeling (1) is necessary for the scale at which land is actually managed and (2) produces estimates with an accuracy and precision affording improved understanding and management of forest ecosystems.

  19. Response of groundwater levels to rainfall and to leaf growth of farm plantations near salt seeps

    NASA Astrophysics Data System (ADS)

    Biddiscombe, E. F.; Rogers, A. L.; Allison, H.; Litchfield, R.

    1985-05-01

    Clearing of native forest has caused a rise in soil water tables and secondary salinisation in south Western Australia. An experiment in reclamation began in May 1976 with the replanting of tree vegetation near salt seeps. Spectral analysis was used to relate the subsequent changes in static water levels of the groundwater to rainfall input and progressive leaf area index of two plantations on a single subcatchment. The upslope static water levels lagged the seasonal rainfall by 3-4 months, whereas the midslope levels lagged rainfall by ˜ 1 month. Increasing leaf area of the plantations corresponded to decreasing groundwater levels in their vicinity.

  20. Biogeochemical Changes Associated With Conversion of Grazed Pastures to Plantation Forests in New Zealand

    NASA Astrophysics Data System (ADS)

    Scott, N. A.; Tate, K. R.; Ross, D. J.; Parfitt, R.; Parshotam, A.; Halliday, J.; McMurtrie, R.

    2001-05-01

    Since the 1930s, large areas of marginally productive pasture and/or scrubland have been converted to plantation forests dominated by Pinus radiata. In the 1990s, up to 100,000 hectares of new plantings occurred each year, many into land used previously for pasture. Current plantation forest area is about 1.7 million hectares. This land-use change impacts many biogeochemical and hydrological processes, and plays an important role in several current environmental issues. Conversion of pasture to plantation forests increases evapotranspiration, and can reduce streamflow and regional water availability. However, afforestation also stabilizes pasture soils that would be highly erodible when covered with pasture vegetation. Soil temperatures are also lower in plantation forests than in pasture, influencing carbon and nitrogen cycling rates. Because of differences in plant litter quality and distribution of carbon inputs to the soil, afforestation often leads to a reduction in soil pH, lower soil carbon turnover rates, lower net N mineralization, lower total mineral soil N, and reduced numbers of soil invertebrates (particularly earthworms). At many sites, these changes can lead to a reduction in mineral soil C stocks, with the reduction sometimes greater than the C accumulated in the forest floor. High N availability associated with pastures can often lead to N leaching losses when tree seedlings are established and uptake of N by pasture grasses inhibited by e.g. herbicide application. We discuss the ability of ecosystem models to simulate these complex biogeochemical changes associated with afforestation, the potential importance of forest management on these changes, and the implications for key environmental issues such as the rate of carbon sequestration in Kyoto forests and decreased emissions of agricultural trace gases.

  1. A comparison between energy transfer and atmospheric turbulent exchanges over alpine meadow and banana plantation

    NASA Astrophysics Data System (ADS)

    Ding, Zhangwei; Ma, Yaoming; Wen, Zhiping; Ma, Weiqiang

    2016-04-01

    Banana plantation and alpine meadow ecosystems in southern China and the Tibetan Plateau are unique in the underlying surfaces they exhibit. In this study, we used eddy covariance and a micrometeorological tower to examine the characteristics of land surface energy exchanges over a banana plantation in southern China and an alpine meadow in the Tibetan Plateau from May 2010 to August 2012. The results showed that the diurnal and seasonal variations in upward shortwave radiation flux and surface soil heat flux were larger over the alpine meadow than over the banana plantation surface. Dominant energy partitioning varied with season. Latent heat flux was the main consumer of net radiation flux in the growing season, whereas sensible heat flux was the main consumer during other periods. The Monin-Obukhov similarity theory was employed for comparative purposes, using sonic anemometer observations of flow over the surfaces of banana plantations in the humid southern China monsoon region and the semi-arid areas of the TP, and was found to be applicable. Over banana plantation and alpine meadow areas, the average surface albedo and surface aerodynamic roughness lengths under neutral atmospheric conditions were ~0.128 and 0.47m, and ~0.223 and 0.01m, respectively. During the measuring period, the mean annual bulk transfer coefficients for momentum and sensible heat were 1.47×10-2 and 7.13×10-3, and 2.91×10-3 and 1.96×10-3, for banana plantation and alpine meadow areas, respectively. This is the first time in Asia that long-term open field measurements have been taken with the specific aim of making comparisons between banana plantation and alpine meadow surfaces.

  2. Short-rotation management of Eucalyptus: Guidelines for plantations in Hawaii. Forest Service general technical report (Final)

    SciTech Connect

    Whitesell, C.D.; DeBell, D.S.; Schubert, T.H.; Strand, R.F.; Crabb, T.B.

    1992-11-01

    A 10-year research and development program was conducted on the island of Hawaii, where nearly 230,000 acres are suitable for growing biomass in short-rotation Eucalyptus plantations. Successful techniques are described for seedling production, plantation establishment (site preparation, weed control, planting), maintenance (weed control, fertilization), biomass yield estimation, and harvest. Basic biological relationships are described to aid decisions on site selection, initial spacing, fertilizer schedules, and rotation length. Environmental issues likely to be faced by growers of Eucalyptus plantations are discussed, including soil erosion, nutrient depletion, and monocultures. Continuing programs for tree improvement, monitoring, and silviculture research are recommeded. Production costs for biomass yields are estimated for three promising management regimes, representing pure Eucalyptus plantings at dense and wide spacings and a mixed species plantation where Albizia is used as a nurse crop to provide nitrogen needed for optimum Eucalyptus growth.

  3. Community structure of earthworms under rubber plantations and mixed forests in Tripura, India.

    PubMed

    Chaudhuri, P S; Nath, Sabyasachi

    2011-09-01

    Studies on community structures of earthworms of rubber (Hevea brasiliensis) plantations and their adjacent mixed forests in West Tripura (India) revealed that both the studied sites harvoured 10 earthworm species. Nine species (Pontoscolex corethrurus, Kanchuria sp 1, Metaphire houlleti, Drawida papillifer papillifer, Drawida assamensis, Gordiodrilus elegans, Eutyphoeus assamensis, Eutyphoeus comillahnus and Eutyphoeus gigas) were common to both. While Octochaetona beatrixwas found only in the rubber plantations, Dichogaster affinis was restricted to the mixed forest only. Earthworms were found mostly within 15 cm depth of soils having mean temperature of 27 degrees C, moisture of 23%, pH of 4.57, organic matter of 1.34% and water holding capacity of 36%. Mean earthworm density in rubber plantations (115 ind. m(-2)) was significantly higher (p = 0.003, t = 3.83) than that in the mixed forests (69 ind. m(-2)) due to dominance of Pontoscolex corethrurus, an exotic species. Numbers of dominant species were two (P. corethrurus and D. assamensis) in the rubber plantations and five (P. corethrurus D. assamensis, D. papilliferpapillifer, M. houlleti and Kanchuria sp 1) in the mixed forests. Compared to the mixed forests, significantly low (p<0.05) Shannon diversity index (H) and species evenness and high index of dominance in the rubber plantation were evaluated. PMID:22319866

  4. Monitoring expansion of plantations in Lao tropical forests using Landsat time series

    NASA Astrophysics Data System (ADS)

    Phompila, Chittana; Lewis, Megan; Clarke, Kenneth; Ostendorf, Bertram

    2014-11-01

    Clearing of native forest for plantation expansion is a significant component of land use change in many tropical regions. The continuing expansion of plantations has many environmental consequences, including the loss and fragmentation of habitat, alteration of nutrient cycling processes, reduction in environmentally sequestered carbon, increased soil erosion and land degradation, and loss of biodiversity. The primary goal of this research was to develop and test remote sensing methods to detect the expansion of plantations in the southern part of the Lao People's Democratic Republic (PDR). We used Landsat satellite imagery acquired between 2003 and 2012. Principal component analysis (PCA) was applied to three Landsat temporal image pairs (2003-2006, 2006-2009 and 2009-2012) to identify areas of change. Change identification accuracy was evaluated by comparison against 1,240 random sample locations which had been independently classified from Google Earth imagery from 2006 and 2012. It was found that one of the principal components detected change in areas of plantation in the study area, with producer's accuracy of 92% and user's accuracy of 79%. This method was relatively easy to implement, involved no image purchase costs, and could be used by ecologists or forestry managers seeking to monitor forest loss or plantation expansion.

  5. Responses of energy partitioning and surface resistance to drought in a poplar plantation in northern China

    NASA Astrophysics Data System (ADS)

    Kang, M.; Zhang, Z.; Noormets, A.; Fang, X.; Zha, T.; Zhou, J.; Sun, G.; McNulty, S.; Chen, J.

    2015-01-01

    Poplar (Populus sp.) plantations have been used broadly for combating desertification, urban greening, and paper and wood production in northern China. However, given the high water use by the species and the regional dry environment, the long-term sustainability of these plantations needs to be evaluated. Currently, the understanding of energy partitioning and canopy resistance to water vapor and CO2 in poplar plantations is limited, impeding an accurate assessment of their true ecosystem functions. This study examined the variability of canopy bulk resistance parameters and energy partitioning over a four-year period encompassing both dry and wet conditions in a poplar (Populus euramericana CV. "74 / 76") plantation ecosystem located in northern China. Available energy (Net radiation Rn minus Soil Heat Flux, G) partitioning to latent (LE) and sensible (H) heat was responsive to climatological drought, with LE/(Rn-G) ranging from 62% in wet years (e.g. 2007 and 2008) to 53% in dry years (e.g. 2006 and 2009), and H/(Rn-G) from 25 to 33% between wet and dry years. Correspondingly, the Bowen ratio (β=H/LE) were 0.83 and 1.57. Surface resistance (Rs) had the greatest response to drought (+43%), but the aerodynamic and climatological resistances did not change significantly (p > 0.05). Partial correlation analysis indicated that Rs was the dominant factor in controlling the Bowen ratio. Furthermore, Rs was the major factor controlling LE during the growing season, even in wet years, as indicated by the decoupling coefficient (Ω = 0.45 and 0.39 in wet and dry years, respectively), and the LE / LEeq ratio ranged from 0.81 and 0.68 in wet and dry years, respectively. In general, the dry surface conditions dominated in this poplar plantation ecosystem regardless of soil water availability suggesting that fast-growing and water use-intensive species like poplar plantations are poorly adapted for the water limited region.

  6. Effects of Successive Rotation Regimes on Carbon Stocks in Eucalyptus Plantations in Subtropical China Measured over a Full Rotation

    PubMed Central

    Li, Xiaoqiong; Ye, Duo; Liang, Hongwen; Zhu, Hongguang; Qin, Lin; Zhu, Yuling; Wen, Yuanguang

    2015-01-01

    Plantations play an important role in carbon sequestration and the global carbon cycle. However, there is a dilemma in that most plantations are managed on short rotations, and the carbon sequestration capacities of these short-rotation plantations remain understudied. Eucalyptus has been widely planted in the tropics and subtropics due to its rapid growth, high adaptability, and large economic return. Eucalyptus plantations are primarily planted in successive rotations with a short rotation length of 6~8 years. In order to estimate the carbon-stock potential of eucalyptus plantations over successive rotations, we chose a first rotation (FR) and a second rotation (SR) stand and monitored the carbon stock dynamics over a full rotation from 1998 to 2005. Our results showed that carbon stock in eucalyptus trees (TC) did not significantly differ between rotations, while understory vegetation (UC) and soil organic matter (SOC) stored less carbon in the SR (1.01 vs. 2.76 Mg.ha-1 and 70.68 vs. 81.08 Mg. ha-1, respectively) and forest floor carbon (FFC) conversely stored more (2.80 vs. 2.34 Mg. ha-1). The lower UC and SOC stocks in the SR stand resulted in 1.13 times lower overall ecosystem carbon stock. Mineral soils and overstory trees were the two dominant carbon pools in eucalyptus plantations, accounting for 73.77%~75.06% and 20.50%~22.39%, respectively, of the ecosystem carbon pool. However, the relative contribution (to the ecosystem pool) of FFC stocks increased 1.38 times and that of UC decreased 2.30 times in the SR versus FR stand. These carbon pool changes over successive rotations were attributed to intensive successive rotation regimes of eucalyptus plantations. Our eight year study suggests that for the sustainable development of short-rotation plantations, a sound silvicultural strategy is required to achieve the best combination of high wood yield and carbon stock potential. PMID:26186367

  7. Effects of Successive Rotation Regimes on Carbon Stocks in Eucalyptus Plantations in Subtropical China Measured over a Full Rotation.

    PubMed

    Li, Xiaoqiong; Ye, Duo; Liang, Hongwen; Zhu, Hongguang; Qin, Lin; Zhu, Yuling; Wen, Yuanguang

    2015-01-01

    Plantations play an important role in carbon sequestration and the global carbon cycle. However, there is a dilemma in that most plantations are managed on short rotations, and the carbon sequestration capacities of these short-rotation plantations remain understudied. Eucalyptus has been widely planted in the tropics and subtropics due to its rapid growth, high adaptability, and large economic return. Eucalyptus plantations are primarily planted in successive rotations with a short rotation length of 6~8 years. In order to estimate the carbon-stock potential of eucalyptus plantations over successive rotations, we chose a first rotation (FR) and a second rotation (SR) stand and monitored the carbon stock dynamics over a full rotation from 1998 to 2005. Our results showed that carbon stock in eucalyptus trees (TC) did not significantly differ between rotations, while understory vegetation (UC) and soil organic matter (SOC) stored less carbon in the SR (1.01 vs. 2.76 Mg.ha(-1) and 70.68 vs. 81.08 Mg. ha(-1), respectively) and forest floor carbon (FFC) conversely stored more (2.80 vs. 2.34 Mg. ha(-1)). The lower UC and SOC stocks in the SR stand resulted in 1.13 times lower overall ecosystem carbon stock. Mineral soils and overstory trees were the two dominant carbon pools in eucalyptus plantations, accounting for 73.77%~75.06% and 20.50%~22.39%, respectively, of the ecosystem carbon pool. However, the relative contribution (to the ecosystem pool) of FFC stocks increased 1.38 times and that of UC decreased 2.30 times in the SR versus FR stand. These carbon pool changes over successive rotations were attributed to intensive successive rotation regimes of eucalyptus plantations. Our eight year study suggests that for the sustainable development of short-rotation plantations, a sound silvicultural strategy is required to achieve the best combination of high wood yield and carbon stock potential. PMID:26186367

  8. Oil palm plantations fail to support mammal diversity.

    PubMed

    Yue, Sam; Brodie, Jedediah F; Zipkin, Elise F; Bernard, Henry

    2015-12-01

    Agricultural expansion is the largest threat to global biodiversity. In particular, the rapid spread of tree plantations is a primary driver of deforestation in hyperdiverse tropical regions. Plantations tend to support considerably lower biodiversity than native forest, but it remains unclear whether plantation traits affect their ability to sustain native wildlife populations, particularly for threatened taxa. If animal diversity varies across plantations with different characteristics, these traits could be manipulated to make plantations more "wildlife friendly." The degree to which plantations create edge effects that degrade habitat quality in adjacent forest also remains unclear, limiting our ability to predict wildlife persistence in mixed-use landscapes. We used systematic camera trapping to investigate mammal occurrence and diversity in oil palm plantations and adjacent forest in Sabah, Malaysian Borneo. Mammals within plantations were largely constrained to locations near native forest; the occurrence of most species and overall species richness declined abruptly with decreasing forest proximity from an estimated 14 species at the forest ecotone to -1 species 2 km into the plantation. Neither tree height nor canopy cover within plantations strongly affected mammal diversity or occurrence, suggesting that manipulating tree spacing or planting cycles might not make plantations more wildlife friendly. Plantations did not appear to generate strong edge effects; mammal richness within forest remained high and consistent up to the plantation ecotone. Our results suggest that land-sparing strategies, as opposed to efforts to make plantations more wildlife-friendly, are required for regional wildlife conservation in biodiverse tropical ecosystems. PMID:26910955

  9. Simulation of Canopy CO2/H2O Fluxes for a Rubber (Hevea Brasiliensis) Plantation in Central Cambodia: The Effect of the Regular Spacing of Planted Trees

    SciTech Connect

    Kumagai, Tomo'omi; Mudd, Ryan; Miyazawa, Yoshiyuki; Liu, Wen; Giambelluca, Thomas; Kobayashi, N.; Lim, Tiva Khan; Jomura, Mayuko; Matsumoto, Kazuho; Huang, Maoyi; Chen, Qi; Ziegler, Alan; Yin, Song

    2013-09-10

    We developed a soil-vegetation-atmosphere transfer (SVAT) model applicable to simulating CO2 and H2O fluxes from the canopies of rubber plantations, which are characterized by distinct canopy clumping produced by regular spacing of plantation trees. Rubber (Hevea brasiliensis Müll. Arg.) plantations, which are rapidly expanding into both climatically optimal and sub-optimal environments throughout mainland Southeast Asia, potentially change the partitioning of water, energy, and carbon at multiple scales, compared with traditional land covers it is replacing. Describing the biosphere-atmosphere exchange in rubber plantations via SVAT modeling is therefore essential to understanding the impacts on environmental processes. The regular spacing of plantation trees creates a peculiar canopy structure that is not well represented in most SVAT models, which generally assumes a non-uniform spacing of vegetation. Herein we develop a SVAT model applicable to rubber plantation and an evaluation method for its canopy structure, and examine how the peculiar canopy structure of rubber plantations affects canopy CO2 and H2O exchanges. Model results are compared with measurements collected at a field site in central Cambodia. Our findings suggest that it is crucial to account for intensive canopy clumping in order to reproduce observed rubber plantation fluxes. These results suggest a potentially optimal spacing of rubber trees to produce high productivity and water use efficiency.

  10. Dissipation of the fungicide hexaconazole in oil palm plantation.

    PubMed

    Maznah, Zainol; Halimah, Muhamad; Ismail, Sahid; Idris, Abu Seman

    2015-12-01

    Hexaconazole is a potential fungicide to be used in the oil palm plantation for controlling the basal stem root (BSR) disease caused by Ganoderma boninense. Therefore, the dissipation rate of hexaconazole in an oil palm agroecosystem under field conditions was studied. Two experimental plots were treated with hexaconazole at the recommended dosage of 4.5 g a.i. palm(-1) (active ingredient) and at double the recommended dosage (9.0 g a.i. palm(-1)), whilst one plot was untreated as control. The residue of hexaconazole was detected in soil samples in the range of 2.74 to 0.78 and 7.13 to 1.66 mg kg(-1) at the recommended and double recommended dosage plots, respectively. An initial relatively rapid dissipation rate of hexaconazole residues occurred but reduced with time. The dissipation of hexaconazole in soil was described using first-order kinetics with the value of coefficient regression (r (2) > 0.8). The results indicated that hexaconazole has moderate persistence in the soil and the half-life was found to be 69.3 and 86.6 days in the recommended and double recommended dosage plot, respectively. The results obtained highlight that downward movement of hexaconazole was led by preferential flow as shown in image analysis. It can be concluded that varying soil conditions, environmental factors, and pesticide chemical properties of hexaconazole has a significant impact on dissipation of hexaconazole in soil under humid conditions. PMID:26276276

  11. Aggregate stability in citrus plantations. The impact of drip irrigation

    NASA Astrophysics Data System (ADS)

    Cerdà, A.; Mataix-Solera, J.; Arcenegui, V.

    2012-04-01

    Soil aggregate stability is a key property for soil and water conservation, and a synthetic parameter to quantify the soil degradation. Aggregation is relevant in soils where vegetation cover is scarce (Cerdà, 1996). Most of the research carried out to determine the soil aggregate stability was done in forest soils (Mataix-Solera et al., 2011) and little is done on farms (Cerdà, 2000). The research have show the effect of vegetation cover on soil aggregate stability (Cerdà, 1998) but little is known when vegetation is scarce, rare or not found such it can be seeing in agriculture soils. Then, aggregation is the main factor to control the soil losses and to improve the water availability. Moreover, agriculture management can improve the soil aggregate characteristics and the first step in this direction should be to quantify the aggregate stability. There is no information about the aggregate stability of soils under citrus production, although the research did show that the soil losses in the farms with citrus plantations is very high (Cerdà et al., 2009), and that aggregation should play a key role as the soils are bare due to the widespread use of herbicides. From 2009 to 2011, samples were collected in summer and winter in a chemically managed farm in Montesa, Eastern Iberian Peninsula. Ten irrigated patches and ten non-irrigated patches were selected to compare the effect of the drip irrigation on the soil aggregate stability. The Ten Drop Impacts (TDI) and the Counting the number of drops (CND) tests were applied at 200 aggregates (10 samples x 10 aggregates x 2 sites) in winter and summer in 2009, 2010 and 2011. The results show that the irrigated patches had TDI values that ranged from 43 to 56 % and that the non-irrigated reached values of 41 to 54 %. The CND samples ranged from 29 to 38 drops in the non-irrigated patches to 32 to 42 drop-impacts in the irrigated soil patches. No trends were found from winter to summer during the three years time period

  12. Effects of increasing forest plantation area and management practices on carbon storage and water use in the United States

    NASA Astrophysics Data System (ADS)

    Chen, G.; Hayes, D. J.; Tian, H.

    2013-12-01

    Planted forest area in the United States gradually increased during the last half century, and by 2007 accounted for about 20% of the total forest area in the southern United States and about 13% in the entire country. Intensive plantation management activities - such as slash burning, thinning, weed control, fertilization and the use of genetically improved seedlings - are routinely applied during the forest rotation. However, no comprehensive assessments have been made to examine the impacts of this increased forest plantation area and associated management practices on ecosystem function. In this study, we integrated field measurement data and process-based modeling to quantitatively estimate the changes in carbon storage, nitrogen cycling and water use as influenced by forest plantations in the United States from 1925 to 2007. The results indicated that forest plantations and management practices greatly increased forest productivity, vegetation carbon, and wood product carbon storage in the United States, but slightly reduce soil carbon storage at some areas; however, the carbon sink induced by forest plantations was at the expense of more water use as represented by higher evapotranspiration. Stronger nitrogen and water limitations were found for forest plantations as compared to natural or naturally-regenerated forests.

  13. Seasonal variation in the biomass and non-structural carbohydrate content of fine roots of teak (Tectona grandis L. f.) plantations in a dry tropical region.

    PubMed

    Singh, K P; Srivastava, K

    1986-06-01

    Seasonal variation in the biomass and total non-structural carbohydrate content (TNC) of fine roots of teak (Tectona grandis L. f.) were studied in 19- and 29-year-old plantations in a dry tropical region. Fine root TNC content was highest during the dry summer (May), and lowest in the early part of the rainy season (July). Generally, seasonal trends in TNC content were the opposite of those in fine root biomass. The TNC concentration of roots increased with diameter and decreased with soil depth. In the 19-year-old plantation, fine root TNC content was approximately 12% higher than in the 29-year-old plantation. PMID:14975904

  14. Impact of soil drought on leaf growth of a teak plantation in a dry tropical region and the subsequent impact of leaf area on both canopy net assimilation and evapotranspiration

    NASA Astrophysics Data System (ADS)

    Tanaka, Katsunori

    2010-05-01

    The current study demonstrated the interannual variations from the beginning of leaf expansion to the peak at a stand level in a dry tropical climate of northern Thailand. Radiative transmittance was measured from March-July in 2001-2008, and seasonal changes in leaf area were qualitatively estimated based on this time series. Soil moisture was also measured, and its influence on leaf growth was shown. Next, a soil-plant-air (SPAC) continuum multilayer model was used to numerically simulate net canopy assimilation (An) and evapotranspiration (ET) for 8 years, to examine the seasonal changes in LAI on An and ET. Two numerical experiments with different seasonal patterns of LAI were carried out using above-canopy hydro-meteorological data as input data. The first experiment involved seasonally varying LAI estimated based on time-series of radiative transmittance through the canopy, and the second experiment applied a constant LAI (or the peak values of LAI) after the flushing. In the first simulation, the simulated transpiration agreed with seasonal changes in heat pulse velocity, corresponding to the water use of individual trees. In the second numerical simulations, the constant LAI increased transpiration at small LAI, particularly immediately after leaf flush. But, the seasonal changes in simulated transpiration were apparently similar to those in observed heat pulse velocity. This implies that soil water, which is balanced in SPAC systems by precipitation, canopy interception, soil evaporation, soil water uptake by transpiration, and discharge, can mainly control the seasonal changes in transpiration. The simulated An became negative under soil drought during the leaf expansion stage in the second simulation, while it became positive or slightly negative even under soil drought in the first simulation. Thus, the limitation of leaf expansion rate caused by soil drought can be favorable for carbon gain.

  15. A comparison between energy transfer and atmospheric turbulent exchanges over alpine meadow and banana plantation

    NASA Astrophysics Data System (ADS)

    Ding, Zhangwei; Ma, Yaoming; Wen, Zhiping; Ma, Weiqiang; Chen, Shiji

    2016-03-01

    Banana plantation and alpine meadow ecosystems in southern China and the Tibetan Plateau (TP) are unique in the underlying surfaces they exhibit. In this study, we used eddy covariance and a micrometeorological tower to examine the characteristics of land surface energy exchanges over a banana plantation in southern China and an alpine meadow in the Tibetan Plateau from May 2010 to August 2012. The results showed that the diurnal and seasonal variations in upward shortwave radiation flux and surface soil heat flux were larger over the alpine meadow than over the banana plantation surface. Dominant energy partitioning varied with season. Latent heat flux was the main consumer of net radiation flux in the growing season, whereas sensible heat flux was the main consumer during other periods. The Monin-Obukhov similarity theory was employed for comparative purposes, using sonic anemometer observations of flow over the surfaces of banana plantations in the humid southern China monsoon region and the semi-arid areas of the TP, and was found to be applicable. Over banana plantation and alpine meadow areas, the average surface albedo and surface aerodynamic roughness lengths under neutral atmospheric conditions were ˜0.128 and 0.47 m, and ˜0.223 and 0.01 m, respectively. During the measuring period, the mean annual bulk transfer coefficients for momentum and sensible heat were 1.47 × 10-2 and 7.13 × 10-3, and 2.91 × 10-3 and 1.96 × 10-3, for banana plantation and alpine meadow areas, respectively.

  16. A new method for determining water uptake in elderberry plantation

    NASA Astrophysics Data System (ADS)

    Tőkei, László; Dunkel, Zoltán; Jung, András

    A considerable quantity of elderberry ( Sambucus nigra L.) fruit gets yearly on the market in Hungary. The decisive majority of this quantity is harvested from feral plants. The area of elderberry plantations is only 150-180 ha in spite of the fact that it would be possible to produce this valuable fruit on larger surface if suitable watering system were applied. The fruit of elderberry is important from the aspect of food industry. The goal of present study is promoting the effective irrigation of elder berry plantation. The experiments were carried out in the Experimental Farm of the University for Horticulture and Food Industry in Szigetcsép from 1989. The measuring of the water demand of elderberry using the heat pulse method was started in 1996. The measurement of the sap-flow in the trunk is a new element of phyto-climate researches. The development of the equipment was started in 1991 and improvement of the method is still going on. In this phase, first of all the connections between sap-flow velocity and meteorological data were investigated. Summarising the experiences of the trials it can be announced that: (1) The water circulation of elder plants principally depends on the conditions of atmosphere. It is barely sensitive to the water content of the soil. (2) The transpiration intensity reacts sensitively to the change of meteorological conditions. (3) The changing rate of the transpiration coefficient is particularly large in certain intervals of the meteorological elements.

  17. Cover crops for erosion control in bioenergy hardwood plantations

    SciTech Connect

    Malik, R.K.; Green, T.H.; Mays, D.

    1996-12-31

    The use of cover crops between tree rows has been suggested as a means of reducing soil erosion in short-rotation woody crops (SRWC) plantations for bioenergy production. This study is designed to test whether cover crops could reduce erosion without significantly reducing the growth and biomass yield of sweetgum (Liquidambar styraciflua L.) planted as the SRWC at a 1.5 X 3 in spacing. Four cover crops, winter rye grass (Lolium multigeonum L., a winter annual grass); tall fescue (Fescuta eliator L., a winter perennial grass); crimson clover (Trifolium incarnatum L., a winter annual legume); and interstate sericea (Lespedeza ameata L., a growing season perennial legume), are tested at two different strip widths (1.22 and 2.44 m) as well as a control with complete competition control. Small berms were built to direct runoff to a sediment fence installed at the down slope ends of each plot. Soil erosion is measured by sediment accumulation near the fence. Height, ground-line diameter and crown width of trees were measured on a monthly basis. During the first growing season all cover crops reduced growth of trees. There were some significant differences among cover crop regimes. Slight differences in soil erosion were detected during the first growing season. The control plots lost more soil per hectare than cover crops, however, strip widths and cover crops did not show any significant difference.

  18. Measurements of transpiration from Eucalyptus plantations, India, using deuterium tracing

    SciTech Connect

    Calder, I.R.; Swaminath, M.H.; Kariyappa, G.S.; Srinivasalu, N.V.; Murthy, K.V.; Mumtaz, J.

    1992-12-31

    Measurements of transpiration from individual trees in Eucalyptus plantations at four different sites in Karnataka, southern India, are presented. These show large (as much as tenfold) differences in the transpiration between pre and post monsoon periods; a reflection of the effects of soil moisture stress in the pre monsoon periods. For trees with diameters at breast height (DBH) less than 10 cm the transpiration rate of individual trees is proportional to the square of the DBH. For trees which are not experiencing soil water stress the daily transpiration rate of individual trees, q, is well represented by the relation: q= (6.6 {+-} 0.3)g m{sup 3}d{sup {minus}1} where g (m{sup 2}) is the tree basal area. On a unit ground area basis the transpiration rate, expressed as a depth per day, is given by the relation: E{sub t}= (0.66 {+-} 0.03)G (mm d{sup {minus}1}) where G (m{sup 2} ha{sup {minus}1}) is the total basal area per hectare. For all the sites studied, although there is evidence for the mining of soil water as roots penetrate deeper depths in the soil each year, there is no evidence for direct abstraction from the watertable.

  19. Rock fragment cover controls the sediment detachment in citrus plantations

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; Keesstra, Saskia; Hamidreza Sadeghi, Seyed; Brevik, Eric; Giménez Morera, Antonio; Novara, Agata; Masto, Reginald E.; Jordán, Antonio; Wang, Juan

    2016-04-01

    conditions. The objective of this research is to determine the impact of the rock fragment cover on soil and water losses in citrus plantations. Within the Corral Roig Soil Erosion Research Station, located in the Municipality of Montesa, 82 plots were selected with different rock fragment cover. In each circular plot of 0.25 m2, a rainfall simulation experiments was carried out at 55 mm h-1 of rainfall intensity during 1 hour under dry conditions in the Summer of 2013 under very dry conditions. It was found that the soil erosion rates are related to percentage of bare soil, and negatively correlated to the rock fragment covers. A cover of 30 % of rock fragments reduces the loss of soil with 81%. Acknowledgements The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603498 (RECARE project). References Cerdà, A. 1999. Parent material and vegetation affect soil erosion in eastern Spain. Soil Science Society of America Journal, 63 (2), 362-368. Cerdà, A., Giménez-Morera, A. and Bodí, M.B. Soil and water losses from new citrus orchards growing on sloped soils in the western Mediterranean basin. Earth Surface Processes and Landforms, 34, 1822-1830. 2009. DOI: 10.1002/esp.1889 Cerdà, A., González-Pelayo, O., Giménez-Morera, A., Jordán, A., Pereira, P., Novara, A., Brevik, E.C., Prosdocimi, M., Mahmoodabadi, M., Keesstra, S., García Orenes, F., Ritsema, C., 2015. The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency - high magnitude simulated rainfall events. Soil Res. (In press) Cerdà, A., Jurgensen, M.F. 2011. Ant mounds as a source of sediment on citrus orchard plantations in eastern Spain. A three-scale rainfall simulation approachCatena, 85 (3), 231-236. DOI: 10.1016/j.catena.2011.01.008 Cerdà, A., Jurgensen, M.F. 2008.The influence of ants on soil and water losses from an orange orchard in

  20. Soil microbial community structure and function responses to successive planting of Eucalyptus.

    PubMed

    Chen, Falin; Zheng, Hua; Zhang, Kai; Ouyang, Zhiyun; Li, Huailin; Wu, Bing; Shi, Qian

    2013-10-01

    Many studies have shown soil degradation after the conversion of native forests to exotic Eucalyptus plantations. However, few studies have investigated the long-term impacts of short-rotation forestry practices on soil microorganisms. The impacts of Eucalyptus successive rotations on soil microbial communities were evaluated by comparing phospholipid fatty acid (PLFA) abundances, compositions, and enzyme activities of native Pinus massoniana plantations and adjacent 1st, 2nd, 3rd, 4th generation Eucalyptus plantations. The conversion from P. massoniana to Eucalyptus plantations significantly decreased soil microbial community size and enzyme activities, and increased microbial physiological stress. However, the PLFA abundances formed "u" shaped quadratic functions with Eucalyptus plantation age. Alternatively, physiological stress biomarkers, the ratios of monounsaturated to saturated fatty acid and Gram+ to Gram- bacteria, formed "n"' shaped quadratic functions, and the ratio of cy17:0 to 16:1omega7c decreased with plantation age. The activities of phenol oxidase, peroxidase, and acid phosphatase increased with Eucalyptus plantation age, while the cellobiohydrolase activity formed "u" shaped quadratic functions. Soil N:P, alkaline hydrolytic nitrogen, soil organic carbon, and understory cover largely explained the variation in PLFA profiles while soil N:P, alkaline hydrolytic nitrogen, and understory cover explained most of the variability in enzyme activity. In conclusion, soil microbial structure and function under Eucalyptus plantations were strongly impacted by plantation age. Most of the changes could be explained by altered soil resource availability and understory cover associated with successive planting of Eucalyptus. Our results highlight the importance of plantation age for assessing the impacts of plantation conversion as well as the importance of reducing disturbance for plantation management. PMID:24494498

  1. CO2 and energy fluxes from an oil palm plantation in Sumatra, Indonesia

    NASA Astrophysics Data System (ADS)

    Meijide, Ana; Herbst, Mathias; Knohl, Alexander

    2014-05-01

    Oil palm plantations are expanding in Indonesia due to global increased demand of palm oil. Such plantations are usually set in previously forested land and in Sumatra, massive transformation of lowland forest into oil palm plantations is taking place. These land transformations have been identified as a potential driver of climate change, as they might result in changes of greenhouse gas (GHG) fluxes. However, very limited information is available on GHG fluxes from oil palm plantations and their sink or source strength at ecosystem scale is yet unknown. An eddy covariance tower was therefore installed in a 2 year old oil palm plantation in the province of Jambi, Sumatra (1° 50' 7'S, 103° 17' 44'E), with the aim of studying carbon dioxide, water and energy fluxes during the non-productive phase of oil palm cultivation. The canopy was not yet closed and trees were around 2m high. The eddy covariance system consists of a Licor 7500A and an ultrasonic Metek Anemometer, operating at 10 Hz and installed on a 7m tower. In addition to the eddy covariance measurements, the site is equipped with a weather station, measuring short and long wave radiation, PAR, rainfall, profiles of air temperature, air humidity and wind speed, soil temperature and moisture and soil heat fluxes. Measurements started in July 2013 until January 2014, in order to capture possible differences which may happen during the dry (July-October) and wet (November-February) seasons. A large CO2 uptake would have been expected at this young oil palm plantation, as palm trees during this period of their cultivation are growing fast. However, our preliminary results show that during the first 5 months of measurements, the ecosystem was a small carbon source (below 10 g CO2 m-2). Latent heat flux was higher than sensible heat flux during the period of study, indicative of the high evaporation taking place. Our results show that both for CO2 and energy fluxes, large differences were observed between the

  2. Flux agreement above a Scots pine plantation

    NASA Astrophysics Data System (ADS)

    Gay, L. W.; Vogt, R.; Bernhofer, Ch.; Blanford, J. H.

    1996-03-01

    The surface energy exchange of 12m high Scots pine plantation at Hartheim, Germany, was measured with a variety of methods during a 11-day period of fine weather in mid-May 1992. Net radiation and rate of thermal storage were measured with conventional net radiometers, soil heat flux discs and temperature-based storage models. The turbulent fluxes discussed in this report were obtained with an interchanging Bowen ratio energy budget system (BREB, at 14 m), two one-propeller eddy correlation systems (OPEC systems 1 and 2 at 17m), a 1-dimensional sonic eddy correlation system (SEC system 3) at 15 m, all on one “low” tower, and a 3-dimensional sonic eddy correlation system (SEC system 22) at 22 m on the “high” tower that was about 46 m distant. All systems measured sensible and latent heat (H and LE) directly, except for OPEC systems 1 and 2 which estimated LE as a residual term in the surface energy balance. Closure of turbulent fluxes from the two SEC systems was around 80% for daytime and 30% for night, with closure of 1-dimensional SEC system 3 exceeding that of 3-dimensional SEC system 22. The night measurements of turbulent fluxes contained considerable uncertainty, especially with the BREB system where measured gradients often yielded erroneous fluxes due to problems inherent in the method (i.e., computational instability as Bowen's ratio approaches -1). Also, both eddy correlation system designs (OPEC and SEC) appeared to underestimate |H| during stable conditions at night. In addition, both sonic systems (1- and 3-dimensional) underestimated |LE| during stable conditions. The underestimate of |H| at night generated residual estimates of OPEC LE containing a “phantom dew” error that erroneously decreased daily LE totals by about 10 percent. These special night problems are circumvented here by comparing results for daytime periods only, rather than for full days. To summarize, turbulent fluxes on the low tower from OPEC system 2 and the adjacent

  3. Contrasting nitrate adsorption in Andisols of two coffee plantations in Costa Rica.

    PubMed

    Ryan, M C; Graham, G R; Rudolph, D L

    2001-01-01

    Fertilizer use in coffee plantations is a suspected cause of rising ground water nitrate concentrations in the ground water-dependent Central Valley of Costa Rica. Nitrate adsorption was evaluated beneath two coffee (Coffea arabica L.) plantations in the Central Valley. Previous work at one site had identified unsaturated zone nitrate retardation relative to a tritium tracer. Differences in nitrate adsorption were assessed in cores to 4 m depth in Andisols at this and one other plantation using differences in KCl- and water-extractable nitrate as an index. Significant adsorption was confirmed at the site of the previous tracer test, but not at the second site. Anion exchange capacity, X-ray diffraction data, extractable Al and Si, and soil pH in NaF corroborated that differences in adsorption characteristics were related to subtle differences in clay mineralogy. Soils at the site with significant nitrate adsorption showed an Al-rich allophane clay content compared with a more weathered, Si-rich allophane and halloysite clay mineral content at the site with negligible adsorption. At the site with significant nitrate adsorption, nitrate occupied less than 10% of the total anion adsorption capacity, suggesting that adsorption may provide long-term potential for mitigation or delay of nitrate leaching. Evaluation of nitrate sorption potential of soil at local and landscape scales would be useful in development of nitrogen management practices to reduce nitrate leaching to ground water. PMID:11577895

  4. [Formation causes of wind damage to Robinia pseudoacacia plantation in Yellow River Delta].

    PubMed

    Cao, Bang-Hua; Zhang, Yu-Juan; Mao, Pei-Li; Li, Cheng-Bo

    2012-08-01

    Based on the investigation of the gale-caused damage to the Robinia pseudoacacia plantation in the Yellow River Delta in June-July 2010, this paper measured the morphological indexes and root system characteristics of fallen trees, gap sizes, and soil compactness, aimed to analyze the formation causes of the wind damage to the plantation. Wind-falling was the main form of the wind damage to the R. pseudoacacia plantation, and the damage was more serious for the trees with the diameter at breast height of 15-20 cm. For the fallen trees, their tree height and their crown width, height, and taper degree increased significantly with the increase of the diameter at breast height, while the height under branch, the ratio of crown width to height, and the ratio of the height under branch to tree height showed no significant change. With the increase of diameter class, root length had a rapid increase first but a slow increase then, while root mass increased gradually. With increasing forest gap area, the number of fallen trees decreased after an initial increase, being the maximum in the gap areas of 100-150 m2. Soil compactness increased with soil depth, but did not show significant changes with the stand diameter class. Increased tree shape factors and suppressed root growth resulting from the increased diameter could be the main factors causing wind-falling, and forest gap played a promotion role. PMID:23189678

  5. Environmental controls of evapotranspiration in a mixed plantation in North China

    NASA Astrophysics Data System (ADS)

    Tong, Xiaojuan; Zhang, Jinsong; Meng, Ping; Li, Jun; Zheng, Ning

    2016-07-01

    The mixed plantation plays an important role in the water cycle in the hilly area of North China. To evaluate the effect of afforestation on the water balance in this region, the temporal variation of evapotranspiration (ET) and environmental controls were investigated based on the eddy flux measurement of water vapor in a 31-year-old mixed plantation from 2006 to 2010. During 5 years, annual ET ranged from 513 to 680 mm, with an average of 579 mm. Growing season ET accounted for 72-82 % of annual ET during the 5-year period and its interannual variation was determined by the number of rainy days. In the non-growing and growing seasons, monthly ET was primarily dependent on monthly mean soil water content and monthly mean net radiation, respectively. Annual mean Priestley-Taylor coefficient (α) was 0.64, and the decoupling factor (Ω) was 0.48. High values of α and Ω implied that ET was energy limited in the growing seasons of 2006-2010. The mean annual ratio of ET to precipitation (ET/P) was 1.10. The density of the mixed plantation was around 50 % higher than the optimal value determined by local water capacity, leading to a large ET/P ratio. The dense plantation needs to be thinned to prevent excessive water loss in the hilly area of North China.

  6. Water use efficiency of a banana plantation in a screenhouse

    NASA Astrophysics Data System (ADS)

    Tanny, J.; Dicken, U.; Grava, A.; Cohen, S.

    2009-04-01

    Shading banana and other orchard crops with screens is becoming increasingly popular in arid and semi-arid regions due to the resulting decreased water use and increased fruit quality. This study focused on measurements of water vapor and CO2 fluxes in a large commercial flat-roof banana screenhouse in northern Israel whose dimensions were 300 m long, 200 m wide and 6 m high. Measurements were conducted using an eddy covariance system deployed on a pole near the center of the screenhouse, allowing a minimum fetch of 100 m in all wind directions. The system measured the three air velocity components, air sonic temperature, air humidity and CO2 concentration. Measurements were conducted during 21 days between July 7th (DOY 189) and August 17th 2007 (DOY 230). During this period the banana plants grew from 2.8 to 4.6 m height and leaf area index increased from 0.5 to 1.8. Additional measurements of net radiation and soil heat flux enabled the analysis of energy balance closure. Energy balance closure analysis gave the regression line Y = 0.85X - 0.5 (R2 = 0.84) where Y represents the consumed energy (latent plus sensible heat fluxes) and X represents the available energy (net radiation minus soil heat flux). This result (slope close to unity) validates the measured evapotranspiration (latent heat flux). Farmer's irrigation increased during the measurement period due to both plant growth and climate variation. Daily evapotranspiration of the plantation increased from 1.7 to 3.2 mm of water during the measurement period. Daily water consumption was on average 70% of the applied irrigation, suggesting that the plantation was over-irrigated. The water use efficiency (WUE) was defined as the total daily mass of CO2 consumed by the plantation per unit mass of water used. Results show that WUE generally increased during the measurement period, implying that larger banana plants were more efficient in using the available water than smaller plants.

  7. Ecological impacts of long-term application of biosolids to a radiata pine plantation.

    PubMed

    Xue, Jianming; Kimberley, Mark O; Ross, Craig; Gielen, Gerty; Tremblay, Louis A; Champeau, Olivier; Horswell, Jacqui; Wang, Hailong

    2015-10-15

    Assessment of the ecological impact of applying biosolids is important for determining both the risks and benefits. This study investigated the impact on soil physical, chemical and biological properties, tree nutrition and growth of long-term biosolids applications to a radiata pine (Pinus radiata D. Don) plantation growing on a Sandy Raw Soil in New Zealand. Biosolids were applied to the trial site every 3 years from tree age 6 to 19 years at three application rates: 0 (Control), 300 (Standard) and 600 (High) kg nitrogen (N) ha(-1), equivalent to 0, 3 and 6 Mg ha(-1) of dry biosolids, respectively. Tree nutrition status and growth have been monitored annually. Soil samples were collected 13 years after the first biosolids application to assess the soil properties and functioning. Both the Standard and High biosolids treatments significantly increased soil (0-50 cm depth) total carbon (C), N, and phosphorus (P), Olsen P and cation exchange capacity (CEC), reduced soil pH, but had no significant effects on soil (0-20 cm depth) physical properties including bulk density, total porosity and unsaturated hydraulic conductivity. The High biosolids treatment also increased concentrations of soil total cadmium (Cd), chromium (Cr), copper (Cu) and lead (Pb) at 25-50 cm depth, but these concentrations were still considered very low for a soil. Ecotoxicological assessment showed no significant adverse effects of biosolids application on either the reproduction of springtails (Folsomia candida) or substrate utilisation ability of the soil microbial community, indicating no negative ecological impact of bisolids-derived heavy metals or triclosan. This study demonstrated that repeated application of biosolids to a plantation forest on a poor sandy soil could significantly improve soil fertility, tree nutrition and pine productivity. However, the long-term fate of biosolids-derived N, P and litter-retained heavy metals needs to be further monitored in the receiving environment

  8. The Plantation Adult Basic Education Program.

    ERIC Educational Resources Information Center

    Southern Mutual Help Association, Abbeville, LA.

    The Plantation Adult Basic Education Program started in 1970 as an alternative to poverty for sugar cane workers in Louisiana. The document discusses the various aspects of the poverty conditions that exist in the area, such as: housing, diet, health, education, and lack of consumer information, and how these existing conditions are to be changed…

  9. Ritual Kinship in a Dominican Republic Plantation.

    ERIC Educational Resources Information Center

    Alum, Rolando A., II

    This paper presents an anthropological description of "compadrazgo" (cogodparenthood) as a sociocultural institution in a state owned sugar cane plantation in the southeastern part of the Dominican Republic. The enthnohistory of the compadrazgo cultural complex is outlined and the institution's roots in ancient Europe before its establishment in…

  10. Strategy for child immunization in Malaysian plantations.

    PubMed

    Sinniah, D; Rajeswari, B; Harun, F; Maniam, C R

    1994-01-01

    An outline is given of a simple cost-effective strategy aimed at the immunization of all children and pregnant women residing in the plantation sector of Malaysia. It is based on a partnership between government, nongovernmental organizations and the private sector, and is supported by UNICEF. PMID:7945748