No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
IMPACT OF CEDRUS LIBANI AFFORESTATION ON SOIL CARBON AND NITROGEN STOCKS IN THE UPPER MEDITERRANEAN BASIN
Abstract
Soils, as the most dynamic and complex components of terrestrial ecosystems, serve as crucial sinks for atmospheric carbon storage and retention. Human interventions in soil management significantly influence the amount of carbon and nitrogen stored or sequestered. This study investigated the effects of afforestation using Cedrus libani A. Rich (Lebanese cedar or Taurus cedar) at two different ages (10 and 25 years) in the Upper Mediterranean basin on soil organic carbon and nitrogen stocks. The afforestation was conducted on previously bare lands for soil conservation purposes. A total of 45 soil samples were collected from topsoil (0–10 cm): 15 samples were randomly taken from two different times (2000 and 2015) afforested areas and 15 from non-afforested (control) land. Soil organic carbon (SOC), total nitrogen (TN), and bulk density (BD) analyses were performed on these samples. To calculate soil organic carbon stocks in tons per hectare, bulk density (BD) was estimated using the SOC and soil mass equation. The results revealed a substantial increase in carbon and nitrogen storage in the afforested areas, depending on tree age. Specifically, organic carbon and nitrogen stocks in the topsoil of 25-year-old and 10-year-old afforestation sites were 65% and 48% higher, respectively, than in control soils. Carbon and nitrogen storage followed the trend: 25-year > 10-year > 0-control. The highest total nitrogen content (0.78%) was observed in 10-year-old cedar afforestation sites. While BD values did not differ significantly among afforested areas, the control areas showed distinct differences from the afforested sites. This study demonstrates that age-protected cedar afforestation significantly enhances carbon and nitrogen sequestration in previously bare soils, highlighting its importance for soil conservation and ecosystem sustainability.
ResearchGate has not been able to resolve any citations for this publication.
Understanding land use/ land cover (LULC) dynamics and the factors that drive these changes is critical for future prediction of landscape structure and development of sustainable and robust land-management strategies and policies. However, little is known about the proximate and underlying factors driving LULC dynamics and perceptions of land users of these dynamics. This study aimed to assess the local land users’ perception of LULC change trends in Gedaref state in Sudan and to determine the approximate and underling drivers that caused such changes in LULC. Initially, we utilized satellite-based LULC maps for the period 1988–2018 that were generated using a robust approach. Subsequently, we used Mann–Kendall trend analysis for the satellite-based LULC changes (area in ha) and the actual crop cultivated area (ha), which were compared with local farmers’ perceptions. A multinomial logistic regression was also employed to determine the major drivers that influence LULC changes in Gedaref state. This was based on a semi-structured questionnaire with 400 respondents. Furthermore, we employed Pearson correlation test and multiple linear regression to assess the effect of change drivers on the area (ha) of the main landscape classes in Gedaref state (i.e., cropland, forest and settlement). Cropland and settlement areas increased (from 78.64 to 89.59%) and (from 0.11 to 0.44%), respectively during the study period. In contrast, forest area decreased (from 1.08 to 0.47%). The results of the semi-structured questionnaire revealed that the satellite-based LULC change trends (area) agreed with respondents’ perceptions. Specifically, 55.5% of the respondents observed an expansion in the cropland area and 96.5% reported an increment in the settlement. Whereas 96.5% of the respondents observed a decline in the forest area. Furthermore, the study shows that the main drivers for LULC changes in Gedaref state were firewood collection, agricultural expansion, charcoal production, settlements, poverty and population growth. The sex of the household head, age, sex of the respondent, education level and farming experience significantly (p ≤ 0.05) influenced the respondents’ perceptions of LULC changes in Gedaref state. Moreover, temperature, amount of rainfall and population growth were positively correlated with the change in cropland and settlement areas (a correlation coefficient (r) ranged between 0.80 and 0.98). While the same variables negatively influenced change in forest areas, with r ranging between 0.47 and 0.88. The findings of this study could be useful for planners and decision-makers for developing coherent land use policies and management strategies.
Sulak alanların %60’ını oluşturan ve yeryüzü toprak organik karbon stokunun %35’inden sorumlu olan subasar orman ekosistemlerinde, makro ve mikro besin stokları bu ekosistemlerin gelişmesi ve sürdürülebilirliği açısından önem kazanmaktadır. Çalışmada, Bursa Karacabey subasar ormanlarında, subasar ve karasal ortamdaki dişbudak meşcerelerinin, ölü örtü ve topraklarının C yoğunluğu, makro ve mikro besin yoğunluğunu ve stoklarını toprak derinlik kademeleri de dikkate alarak belirlemektir. Ölü örtü C, N, P, K, Ca, Mg ve S stoku sırasıyla 1522, 52, 62, 123, 915, 211 ve 110 kg/ha olarak subasar ortamda belirlenirken, karasal ortamda bu değerler N hariç önemli derecede daha düşük olup, sırasıyla 829, 61, 51, 88, 538, 129 ve 61 kg/ha olarak belirlenmiştir. Ölü örtü mikro besin stoklarıda subasar ortamda karasal ortama göre daha yüksek bulunmuştur. Toprak C ve makro besin stoklarıda (N dahil) subasar ortamda daha yüksek bulunmuştur. Topraktaki C, N, P, K, Ca, Mg ve S stoku sırasıyla 246, 27, 6, 85, 104, 188 ve 6 ton/ha olarak subasar ortamda belirlenirken, karasal ortamda bu değerler sırasıyla 233, 24, 5, 77, 177 ve 6 ton/ha olarak belirlenmiştir. Toprak mikro besin (Fe, Mn, Na, Cu, Zn, Cl, Ni ve Co) stoklarıda subasar ortamda karasal ortama göre daha yüksek bulunmuştur. Ek olarak, ölü örtü karbon ile makro ve mikro besin stoklarının meşcere yaşına bağlı olarak azaldığı, topraktaki stoklarının ise artış gösterdiği tespit edilmiştir. C ve N’un en fazla üst topraklarda (0-30 cm) stoklandığı (sırasıyla %71 ve %61), diğer makro ve mikro besinlerin ise alt topraklardaki (30-100 cm) stoklarının, üst topraklardan daha fazla olduğu belirlenmiştir. Sonuçlar, atmosferik karbondioksiti ve azotu tutma ve depolama kapasiteleri nedeniyle iklim değişikliğinin azaltılmasında önemli bir role sahip, subasar orman ekosistemlerinin karbon ve besin döngülerini ve stoklarını anlamaya ve modellemeye faydalı sayısal bilgiler sağlaması açısından önemlidir.
Accelerating urbanization and unplanned excessive human pressure are increasing changes in major land use. These transitions cause long-term negative transformations in rural systems. This study was conducted to examine the changes in some soil properties and carbon stocks of lands that were converted from forest to cropland 30 years ago in ten different villages in the Karaisalı district of Adana, Türkiye. A total of 360 disturbed and undisturbed soil samples were taken from two depth levels (0–30 cm and 30–60 cm) from the soil pits in the adjacent forest and converted to cropland and agricultural areas. Soil organic carbon and bulk density analyses were performed on all soil samples. According to the data obtained from the topsoil (0–30 cm) 101.56 tC ha−1, 69.06 tC ha−1, and 66.25 tC ha−1 carbon were stored in the topsoil of the forest, and converted to cropland and agricultural area, respectively. There has been an average of 32% reduction in soil carbon stocks in converted cropland from degraded forest areas. Dramatic reduction in carbon stocks occurred in the topsoil (0–30 cm). Policymakers need to plan their land-use management policies to take into account the ecological consequences of the land-use transition.
Long‐term carbon (C) sequestration in terrestrial vegetation and soil is mediated by soil nitrogen (N) supply. Afforestation is regarded as a global‐scale solution to climate change; thus, resolving the role of N in either facilitating or reducing the long‐term C benefits of this practice has essential implications to maximize its C sink potential. The impacts of afforestation on soil C, N, and their stoichiometric ratio have been widely explored but what regulates these impacts remains unclear at regional and global scales. In this study, we conducted an intensive field sampling investigation including 610 pairs of afforested and control plots in northern China and extensively compiled a global data set containing 211 afforested‐control pairs worldwide to evaluate responses of soil N concentrations and C:N ratios to afforestation and further explored their major regulator. We identified a soil N threshold, the inflection point where afforestation changes from increasing to decreasing soil C and N, which was 0.86 (95% CI: 0.81–0.91) kg N m⁻² in 0–1 m depth. Changes in soil C:N ratios with afforestation were mediated by initial relative abundance of soil C and N and types of mycorrhiza associated with planted trees. Increases in soil C:N were mostly driven by trees with ectomycorrhizal associations but did not change for those associated with arbuscular mycorrhizal fungi. These results provide a data‐based understanding on soil C and N dynamics following afforestation and its underlying mechanisms and further highlight the importance of site selection based on initial soil properties in future afforestation.
Simple Summary
Minimizing the effects of climate change by reducing GHG emissions is crucial and can be accomplished by truly understanding the carbon footprint phenomenon. This study aims to improve the understanding of carbon footprint alteration due to agricultural management and fertility practices. It provides a detailed review of carbon footprint management under the impacts of environmental factors, land use, and agricultural practices. The results show that healthy soils have numerous benefits for the general public and especially farmers. These benefits include being stable and resilient, resistant to erosion, easily workable in cultivated systems, good habitat for soil micro-organisms, fertile and good structure, large carbon sinks, and hence lower carbon footprint. Intensive tillage is harmful to soil structure by oxidizing carbon and causing GHG emissions. If possible, no-till; if not, minimum tillage frequency and depth of tillage, and optimum moisture are recommended. The soil should be at an appropriate level of moisture when tillage takes place. Diverse cropping systems are better for the soil than monocultures. Minimizing machinery operations can help to avoid soil compaction. Building soil organic carbon in the most stable form is the most efficient practice of sustainable crop production.
Abstract
Global attention to climate change issues, especially air temperature changes, has drastically increased over the last half-century. Along with population growth, greater surface temperature, and higher greenhouse gas (GHG) emissions, there are growing concerns for ecosystem sustainability and other human existence on earth. The contribution of agriculture to GHG emissions indicates a level of 18% of total GHGs, mainly from carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Thus, minimizing the effects of climate change by reducing GHG emissions is crucial and can be accomplished by truly understanding the carbon footprint (CF) phenomenon. Therefore, the purposes of this study were to improve understanding of CF alteration due to agricultural management and fertility practices. CF is a popular concept in agro-environmental sciences due to its role in the environmental impact assessments related to alternative solutions and global climate change. Soil moisture content, soil temperature, porosity, and water-filled pore space are some of the soil properties directly related to GHG emissions. These properties raise the role of soil structure and soil health in the CF approach. These properties and GHG emissions are also affected by different land-use changes, soil types, and agricultural management practices. Soil management practices globally have the potential to alter atmospheric GHG emissions. Therefore, the relations between photosynthesis and GHG emissions as impacted by agricultural management practices, especially focusing on soil and related systems, must be considered. We conclude that environmental factors, land use, and agricultural practices should be considered in the management of CF when maximizing crop productivity.
Background
Depression areas are essential structural components of Karst ecosystems. Their influence in the carbon and nitrogen dynamics under different land uses, which could be effectively used to define management strategies aiming to combat global warming, however, is not clear. This study investigated the changes in selected soil attributes across four land use types (forest, degraded forest, rangeland and cropland) both in depressed and non-depressed areas in a karst ecosystem in Kahramanmaras, Turkey. Soil attributes investigated in this study included soil pH, soil moisture (SM), soil organic carbon (SOC), total nitrogen content (TN), available water (AW), hydraulic conductivity (HC), root rate (RR) and C/N ratio.
Results
Discriminant analyses showed that N, AW, SOC, pH and landuse were the most effective variables affecting the distinction between depression and none-depression areas in karstic ecosystems. According to the structural matrix, the most important single factor affecting the distinction between depression and none-depression areas was SOC, with a correlation coefficient of 0.62. Highest values for SOC, TN and other attributes were found in forest and rangeland land use types, while minimum values were found in cropland land use in most comparisons. Depression areas reduced the negative effects of land use in terms of C, TN, C/N, SM, and RR.
Conclusion
As a result, while constructing restoration plans, the study area should be evaluated from a geo-ecological perspective. Ecological capabilities of depression areas should be considered especially in karst environments.
Keywords:
Depression area; Soil management; Karst environment; Discriminant analysis; Carbon; Nitrogen
Natural grasslands represent the second largest ecosystem in Turkey. However, the impact of varying nitrogen (N) fertilization rates on overall soil health indicators have not been reported in the country. A 2-year study was conducted in the Kahramnmaraş Plateau region in Turkey to evaluate the impacts of seven N application rates [i.e., 0 (N0), 50 (N50), 100 (N100), 150 (N150), 200 (N200), 250 (N250), and 350 (N350) kg N ha ] on physical, chemical, and biological parameters of soil health. Nitrogen addition decreased bulk density by 8–12% and increased aggregate stability by 3–5% and EC up to 110%. Application of ≥ 100 kg N ha increased soil porosity up to 6.7%. Soil pH and C:N ratios were not affected by N addition. The lowest plant available water occurred with the N0 and N50 treatments, decreasing around 24% and 17% compared to N300. Soil organic carbon, total nitrogen, and C and N stocks increased with increasing N addition. Application of N300 rates increased C stocks between 4 and 34%, and N stocks between 15 and 22% compared to all other treatments. Compared to control, N250 increased microbial biomass carbon by 349% and nitrogen by 250%. Microbial respiration in the N250 and the N300 treatments was 97% and 129% greater than control. The addition of N fertilization for the first time in a grassland ecosystem with a previous history of long-term overgrazing, even at low rates, positively impacted several parameters of soil health, a positive impact that could ensure greater sustainability of these fragile systems over the long term.
Afforestation is economically and ecologically important for protecting land and improving soil quality. This study evaluates how soil basal respiration, physicochemical and microbiological characteristics are affected by parent material variety in afforesting degraded areas. For this, some soil physical and chemical parameters, microbial respiration (MR), soil microbial biomass carbon and microbial indexes (Cmic/Corg and MR/Cmic) were determined. The results showed that the physical, chemical and microbiological properties of the soil formed from limestone were better than those of the basaltic-andesite soil. An independent samples t-test demonstrated that the afforested area on the limestone parent material had significantly higher microbial biomass C than the basaltic-andesite parent material. The microbial quotient (Cmic/Corg) of the limestone soil was positively affected by afforestation. In addition, the highest basal respiration value (1.01 ± 0.33 CO2–C 10−2 µg g−1 h⁻¹) was observed for the limestone at the topsoil. The lowest metabolic quotient values were determined for the basaltic-andesite parent material on both topsoil and subsoil (1.99 and 1.42 μg CO2-C mg Cmic⁻¹ h⁻¹, respectively). This study revealed the importance of determining the parent material and its soil characteristics for successfully managing forest applications in degraded areas. Limestone soil sequesters more carbon and promotes microbial activities with a higher Cmic/Corg than the basaltic-andesite soil. Furthermore, the microbial quotient remained low during the 10 years in which the forest was in its sapling stage.
Bu çalışma, Sinop-Boyabat İlçesindeki açık
alan topraklarının bazı fiziksel ve kimyasal özellikleri ile erozyon
eğilimlerinin belirlenmesi amacıyla yapılmıştır. Bu kapsamda açık alanlardan 30
adet toprak çukuru açılarak üst (0-20 cm) ve alt (20-40 cm) derinlik
kademelerinden toplam 60 adet toprak örneği alınmıştır. Alınan örnekler analize
hazır hale getirilerek bazı fiziksel (kum, toz, kil, tarla kapasitesi, solma
noktası, faydalanılabilir su kapasitesi) ve kimyasal (pH, EC, organik karbon,
kireç) toprak özellikleri ile erodibilite indeksleri (kil oranı, kolloid/nem
ekivalanı, erozyon oranı, dispersiyon oranı) belirlenmiştir. İncelenen
topraklar balçıklı kil tekstürde, kireçli ve hafif alkalen karakterde olduğu
belirlenmiştir. Örnek alanlardaki toprakların bazı erodibilite indeksleri üst
ve alt toprak derinliğinde sırasıyla kolloid nem ekivalanı için 1.70, 1.65, dispersiyon
oranı için %24.78, %23.16 ve erozyon oranı için 14.93, 14.51 olarak
belirlenmiştir. Bu değerlere göre erozyon eğilim sınır değerleri esas
alındığında, çalışma alanı topraklarının dispersiyon oranı ve erozyon oranı
bakımından erozyona duyarlı, kolloid nem ekivalanı bakımından ise erozyona
dayanıklı olduğunu tespit edilmiştir. Araştırma sonuçları çalışma alanında
arazi bozulmasının en önemli sebeplerinden birinin su erozyonu olduğunu
göstermektedir. Üzerinde herhangi bir bitki örtüsü bulunmayan toprakların önlem
alınmaması durumunda eroziv yağışlarla kolaylıkla taşınabileceği
anlaşılmaktadır.
The biogeochemical cycles of carbon (C) and nitrogen (N) connect all the abiotic and biotic components of ecosystems to one another in a holistic way. As such, the spatial and temporal dynamics of C and N budgets are closely coupled with variations in such ecosystem processes as productivity, nutrient cycling, stability, succession and biodiversity. In turn, the cycling rates of C and N are affected by the type, magnitude, severity and frequency of natural and anthropogenic disturbances, which induce changes in the structure and function of ecosystems locally and regionally, and which may endanger the sustainability of ecological goods and services globally. C and N budgets are, therefore, significant ecosystem-level indicators that can signal deviations from sustainable ecosystem management under current and changing patterns of human disturbances. Thus, they can assist in evaluating the potential effects of human disturbances on the structure and function of ecosystems, and in developing preventive and mitigative measures in decision- and policy-making. Examples are provided by process-based models to quantify regional C and N dynamics as indicators of sustainability for cropland, drastically disturbed (coal surface-mined land) and urban ecosystems in the State of Ohio in the American Midwest.
Long-term agricultural field experiments provide relevant information for questions being asked about the sustainability of managed forests, particularly as management regimes become more intensive. In this paper, concepts and criteria related to sustainable site productivity are reviewed and findings from a range of long-term agricultural field experiments are evaluated. Based on this evaluation, the following site productivity principles are identified: (1) soil organic matter is the link between most management systems and sustainable site productivity; (2) nutrient deficiencies can be corrected; (3) soil texture is a key variable affecting soil organic matter and site productivity; (4) return of crop residues enhances soil organic matter and site productivity; and (5) productive cropping systems have environmental benefits. While technological advances have proven to be highly successful for enhancing long-term crop yields, they also have the potential to mask underlying declines in site productivity. This hypothesis needs to be rigorously tested.Agricultural field experiments show that crop productivity can be sustained for long time periods when appropriate management approaches are applied. Management requirements to achieve sustainability differ, however, depending on site-specific edaphic and climatic characteristics and the needs of the crop. Site productivity principles derived from agricultural field studies are also highly relevant to sustaining site productivity of managed forests. Several characteristics of managed forests should be considered when extrapolating conclusions from agricultural experiments. These include harvest removals of biomass and nutrients, residue type and distribution, management and system characteristics, and soil types used. Many characteristics associated with even intensively managed forests are sought as goals of conservation cropping systems and should contribute toward sustaining long-term site productivity.
This study investigated the effects of black locust (Robinia pseudoacacia L.), mixed species plantation (MSP) [black locust (R. pseudoacacia L) and stone pine (Pinus pinea L.)] on surface soil properties in eroded clay soils. Three land use types were selected; black locust plantation area (BLP), mixed species plantation (MSP), and adjacent bare fields (control site) (ABA), in a semi-arid region in Artvin, Turkey. The experimental design at each site was a randomized complete block with four replications in each study area. Five disturbed and five undisturbed soil samples were randomly taken at a soil depth of 0–10 and 10–20cm in each plot. At 0 to 10cm soil depth in the BLP and MSP sites, and compared to the control site, field capacity (FC), permanent wilting point (PWP), plant available water (PAW), saturated hydraulic conductivity (Ksat), soil organic matter (SOM), total nitrogen (TN), P2O5, Ca were significantly greater, while bulk density (Db) and C:N ratio were significantly lower. SOM, PAW, TN, Ec, Mg and Ksat decreased significantly in both sites (BLP and MSP), while clay increased significantly in MSP, and PWP and Db increased significantly with soil depth in BLP site. As a result: Althought these species didn't showed good growth in the study area black locust plantation (BLP) and mixed species plantation (MSP) had a positive impact on surface soil properties in clay soils in eroded sites. The planting of “black locust” and “black locust+stone pine” can be useful in soil reclamation projects in this type of eroded site in semi-arid regions.
The study of sustainable land use is complex and long-term experiments are required for a better understanding of the processes
of carbon stabilization. Objectives were (i) to describe for four long-term experiments the effects of fertilization and soil
management on crop yields and the dynamics of soil organic carbon (SOC) and total N, and (ii) to discuss the usefulness of
models for a better understanding of the underlying processes. Data of soil organic carbon and total N of four long-term experiments
in Germany and China which studied the effect of fertilization (Bad Lauchstädt, Darmstadt) and tillage (Göttingen, Quzhou)
were evaluated and soil organic carbon fractionation was carried out. The Rothamsted Carbon Model was used for a description
and prediction of soil organic carbon dynamics as affected by fertilization and tillage in Bad Lauchstädt and Quzhou. The
type of fertilizer added at common rates — either mineral N or farmyard manure — affected the crop yields only slightly, with
slightly lower yields after manure application compared with mineral N fertilization. For both fertilization trials, manure
applications at common rates had beneficial effects on soil organic carbon stocks in the labile pool (turnover time estimated
as <10 years) and to a greater extent in the intermediate pool (turnover time estimated to be in the range of 10 to 100 years).
A comparison of the effects of conventional tillage, reduced tillage and no-tillage carried out in Göttingen and Quzhou indicated
only small differences in crop yields. Reduced tillage in Göttingen resulted in an increased C storage in the surface soil
and C was mainly located in the mineral-associated organic matter fraction and in water-stable macro-aggregates (>0.25 mm).
For Quzhou, no-tillage and conventional tillage had similar effects on total C stocks, with a greater spatial variability
in soil organic carbon stocks in the no-tillage plots. Modeling required site-specific calibrations for the stock of inert
organic matter for each of the sites, indicating that not all carbon stabilization processes are included in the model and
that application of a model to a new site may also need site-specific adjustments before it can be used for predictions. After
site-specific calibration, however, model predictions for the remaining treatments were generally accurate for the fertilization
and tillage trials, which emphasizes the importance of temperature, moisture, soil cover and clay content on the decomposition
dynamics of soil organic carbon and the significance of amounts and quality of carbon inputs in the soil for maintaining or
increasing soil organic carbon stocks in arable soils.
Keywordssoil organic matter–C dynamics–Rothamsted carbon model–tillage–fertilization–soil organic carbon (SOC)
Topography is a key factor that affects edaphic, climatic, and biotic factors directly or indirectly. Relationships between Compound Topographic Index (CTI) model and soil properties were investigated in order to determine the ecological potential of the area in order to plan the sustainability of the fertile lands and the rehabilitation of the degraded areas in the study area. Totally 84 soil samples (0–20 cm) collected from different land use types (forest, cropland, rangeland) in Karst Mountain, Andırın-Kahramanmaras, Turkey. The CTI distributions are generated from digital elevation data of 12 m resolution obtained from AlosPalsar Satellite images. Although CTI values changed to Forest> Cropland> Rangeland, the highest correlation was found between CTI and soil moisture content in rangeland (R² = 0.81). Lower correlations were found with other land uses (R² = 0.63 in Cropland and R² = 0.31 in Forest). CEC and Clay content were found to have a significant (p < 0.01) positive correlation with Curvature. Despite a distinctive topographic structure of karst ecosystems, these correlations verified the influence of topography on soil properties. CTI, which has strong correlations with soil moisture content can be used in planning reclamation processes of degraded karst ecosystems.
Eroded bare land stabilization is important to reduce soil erosion and stimulate soil carbon (C) sequestration for improved soil biochemical quality in hillslope soils. This study investigated the effectiveness of wattle fencing as a bioengineering tool to improve soil stabilization, soil physicochemical properties and soil organic C dynamics and reduce soil erodibility in the Boyabat mountain regions of Turkey with rough and over-steepened slope (5 0-70 %). Wattle fence treatments were developed in the area of 50 ha in the spring season of 20 10 and surface (0-20 cm) and subsurface soil (2 0-40 cm) samples were taken in Spring (2 01 5). Results revealed that compared to control with bare slope, wattle fencing significantly improved some soil physicochemical, and microbial properties and erodibility indices by increasing clay ratio, dispersion ratio, and aggregate stability index in surface and subsoils. Wattle fencing enhanced plant available water contents more on the surface than in subsoils. Wattle fencing also increased microbial biomass C contents by 55 % and 43 % in surface and subsurface soils, respectively. Soil organic C followed similar trends; however, they were indifferent between sampling depths for the control soils. Soil organic C stocks and aggregate stability index were significantly positively correlated and seem ed to be better predictor of positive effects of wattle fencing on soil structural stability, erodibility and associated properties. We found positive effects of soil organic C contents on microbial biomass C and soil-water relations suggesting the restoration of soil biological functions and favorable influence on soil water retention following wattle fencing. Although sparse vegetation was observed in the research area, our study emphasizes performing further research to understand the effects of wattle fencing along with afforestation with native vegetation on soil erosion rates on a long-term basis by considering the variability in edaphic and environmental factors.
Thinning is a common forest management practice. However, its impact on soil organic carbon (SOC) stocks is still unknown. Therefore, we conducted a meta-analysis of 270 measurements from 77 articles to evaluate the effect of forest thinning on SOC stocks in mineral soil (0–30 cm) across planted forests in China. The results showed that, compared to reference (non-thinned) plantations, thinning significantly increased SOC stocks in planted forests by 7.2%. Among different thinning intensities, moderate thinning (35–55% of thinning intensity) increased SOC stocks in planted forests (+16.1%) more than other levels of thinning intensity. However, the positive effect of thinning on SOC stock was significant > 5 years after harvesting. In the humidity-restricted areas (humidity index (HI) < 30), the increase in SOC stocks after thinning was significantly higher than that of other areas. In addition, thinning increased the sensitivity (i.e. slope value) of soil total nitrogen (TN) stocks changes to SOC stocks. Therefore, we conclude that forest thinning strategy is potentially a viable silvicultural measure to increase SOC fixation in planted forests. Our results provide a reference for the formulation and implementation of future forest management strategies.
A significant area of the oak forests in Turkey has been historically managed by short-rotation coppicing for wood production. Coppice management was almost abandoned in Turkey in 2006 and so investigating its impact on forest carbon (C) sequestration has become an important issue. Therefore, we investigated the net effect of this change in management on C sequestration by oak forests in Turkey using field measurement data and a forest C model (Forest Biomass and Dead organic matter Carbon (FBDC) model). The FBDC model estimated the annual forest C dynamics and considered the effect of the substitution of wood for fossil fuels under two management scenarios over a 100-year period: (1) abandoning coppice (no management) and (2) continuing coppice (20-year-interval harvest). The field measurement data were used to parameterize the FBDC model to the study sites and to verify the simulated C stocks. Continuing coppice management constrained an increase in the C stocks (116.0-140.3 Mg C ha-1) and showed a mean annual C sequestration of 0.6 Mg C ha-1 yr-1 if wood was substituted for fossil fuels. In contrast, abandoning coppicing practices increased the level of forest C stocks (128.1-236.2 Mg C ha-1), enhancing the mean annual C sequestration to 1.1 Mg C ha-1 yr-1. Accordingly, the abandonment of coppice management increased the mean annual C sequestration by 0.5 Mg C ha-1 yr-1 in the long-term. However, sensitivity analysis showed a possibility of a larger difference in C sequestration between the two scenarios due to a decrease in the stand productivity by repeated coppices and a high likelihood of a lower substitution effect. The verification supported the scientific reliability of the simulation results. Our study can provide a scientific basis for enhancing C sequestration in coppice forests.
Land take (i.e., increase in settlement area over time) and soil sealing (i.e., permanent covering of land by completely or partly impermeable material) associated with urbanization are increasingly affecting the soil carbon (C) stock, consisting of soil organic carbon (SOC) and soil inorganic carbon (SIC). The soil C balance in urban areas is altered, in particular, by physical disturbance during construction activities, covering by impervious layers, and additions of natural and technogenic materials. In the top 100 cm, land take may result in a loss of up to 66% of the natural SOC stock and a gain of up to 203%. Otherwise, soil sealing may only slightly alter SOC stocks to 100-cm depth but may also result in an increase by 184% compared to natural soils. Further, additions of calcareous demolition waste may drastically alter the SIC stocks, especially through formation of secondary carbonates. However, little quantitative evidence on the effects of land take and sealing on soil C is available. Nevertheless, soils affected by land take and those beneath sealed surfaces are part of urban ecosystems, and their C storage must be studied as urbanization is projected to become the dominant global land transformation.
Sustainable management of soils is needed to accomplish many of the United Nations’ Sustainable Development Goals, but it can be problematic in practice as soils are complex and to manage them sustainably requires the co-operation of multiple stakeholders on various level of society. We present the outcome of a transdisciplinary approach towards indicator development, where we created a set of soil indicators for sustainable development with stakeholder group participation from scientists, policymakers and soil practitioners. The groups evaluated 49 indicators, through a Delphi survey technique, and selected a set of 30 indicators. Of these 14 were common to all stakeholder groups and represented a final set of core soil indicators for sustainable development. The Delphi survey did suffer from high attrition rate and low response rate, especially among the policy makers, which limits somewhat its findings. Nevertheless, the survey illustrated the usefulness of relevant stakeholder involvement in an indicator development process and the role of survey based instruments in aiding the selection of common indicators, whilst showing the different views of stakeholders groups. Given that the stakeholder groups have to consider a multitude of variables and impacts on soil and may have different focus and management goals in mind, a process such as this can serve as a starting point for discussion between stakeholder groups on various levels of governance about how to manage soil sustainably and help to fulfil the UN’s Sustainable Development Goals
This multidisciplinary special issue examines the contemporary rural restructuring in China, focusing on spatial restructuring, economic restructuring and social restructuring and the key challenges for rural areas, whether at local, regional, national or international level. The contributions to this special issue provide conceptual–theoretical and empirical takes on rural restructuring in China. However, the volatility and complexity of rural restructuring in China will present ongoing challenges for further research on the restructuring of rural China. In view of this, this themed edition makes a compelling call for more systematic research of rural restructuring based on extensive disciplinary interaction. This special issue is published to coincide with the 33rd International Geographical Congress (IGC) of IGU in Beijing.
Soil erosion is a major socio-economic and environmental problem in Turkey. Almost 86% of the land in Turkey has suffered various degrees of soil erosion. The objective of this study was to determine whether differences in tree species affect soil characteristics and microbial activity in degraded soils. Results from this study showed that organic C (Corg) was highest in the black locust soil at 0–20 cm depth and lowest in the bare land. Microbial biomass C (Cmic) increased in the order black locust > Scotch pine > bare land at two soil depths. One-way ANOVA demonstrated that afforested soils contain significantly higher microbial biomass C than those in the bare land soils. Microbial quotient (Cmic/Corg) of soils are positively influenced by afforestation as the bare land soils exhibited lower microbial quotient than the associated Scotch pine and black locust soils. Microbial communities in black locust soils were energetically more efficient (had a lower qCO2) with a higher Cmic/Corg compared to those in Scotch pine soils. However, the microbial quotient in our study was still below range and cannot reach equilibrium again 15 years after afforestation. Restoration of degraded lands could be a long-term process from microbial activity in the observed regions.
• Key message
Simulated and observed carbon stocks in Scots pine forests varied considerably with stand age. The contribution of biomass to the total forest carbon stocks increased and that of dead organic matter decreased with increasing stand age.
• Context Understanding changes in forest carbon stocks over time is important to estimate carbon inventory. Although Scots pine (Pinus sylvestris L.) is a main species in Turkey, studies on such changes are still lacking.
• Aims We aimed to estimate the changes in carbon stocks, with stand age, of Scots pine stands in Turkey using field work data and a forest carbon model (FBDC model).
• Methods Biomass and dead organic matter carbon stocks were investigated to adjust the forest carbon model and to verify the model estimates. Forest carbon stocks with regards to stand age were simulated.
• Results The simulated carbon stocks were generally in clear agreement with the observed values on a stand scale. Changes in simulated and observed carbon stocks of biomass and dead organic matter varied with stand age. The contribution of biomass to total forest carbon stocks increased, and that of dead organic matter decreased, with increasing stand age.
• Conclusion We found that the carbon stocks in each pool and their contribution to the total forest carbon stocks varied with stand age. Our results are expected to contribute to the understanding of annual changes in the carbon stocks of Turkish forests.
As the largest pool of terrestrial organic carbon, soils interact strongly with atmospheric composition, climate, and land cover change. Our capacity to predict and ameliorate the consequences of global change depends in part on a better understanding of the distributions and controls of soil organic carbon (SOC) and how vegetation change may affect SOC distributions with depth. The goals of this paper are (1) to examine the association of SOC content with climate and soil texture at different soil depths; (2) to test the hypothesis that vegetation type, through patterns of allocation, is a dominant control on the vertical distribution of SOC; and (3) to estimate global SOC storage to 3 m, including an analysis of the potential effects of vegetation change on soil carbon storage. We based our analysis on >2700 soil profiles in three global databases supplemented with data for climate, vegetation, and land use. The analysis focused on mineral soil layers. Plant functional types significantly affected the v...
This chapter discusses the magnitude and dynamics of the soil organic carbon (SOC) and soil inorganic carbon (SIC) pools. The chapter also describes the impact of different land uses and management systems on these pools as sources or sinks of C in relation to the global C cycle and the potential greenhouse effect. The principal objective of the chapter is to collate and synthesize available information on the soil C pool, historic loss of the soil C pool, the impact of land use and management practices that make the soil a source or sink for C, and the potential of world cropland soils to sequester C and mitigate the accelerated greenhouse effect. The strategy of soil C sequestration is a short-term, a partial solution to the potential risk of the accelerated greenhouse effect. Soil C sinks, as a major component of the net biome productivity, are important over short periods of time, but are not enough on a long-term basis to offset fossil-fuel emissions.
Quantifying changes in soil C may be an important consideration under large-scale afforestation or reforestation. We reviewed global data on changes in soil C following afforestation, available from 43 published or unpublished studies, encompassing 204 sites. Data were highly variable, with soil C either increasing or decreasing, particularly in young (<10-year) forest stands. Because studies varied in the number of years since forest establishment and the initial soil C content, we calculated change in soil C as a weighted-average (i.e. sum of C change divided by sum of years since forest establishment) relative to the soil C content under previous agricultural systems at <10, >10 and <30 cm sampling depths. On average, soil C in the <10 cm (or <30 cm) layers generally decreased by 3.46% per year (or 0.63% per year) relative to the initial soil C content during the first 5 years of afforestation, followed by a decrease in the rate of decline and eventually recovery to C contents found in agricultural soils at about age 30. In plantations older than 30 years, C content was similar to that under the previous agricultural systems within the surface 10 cm of soil, yet at other sampling depths, soil C had increased by between 0.50 and 0.86% per year. Amounts of C lost or gained by soil are generally small compared with accumulation of C in tree biomass. The most important factors affecting change in soil C were previous land use, climate and the type of forest established. Results suggest that most soil C was lost when softwoods, particularly Pinus radiata plantations, were established on ex-improved pastoral land in temperate regions. Accumulation of soil C was greatest when deciduous hardwoods, or N 2 -fixing species (either as an understorey or as a plantation), were established on ex-cropped land in tropical or subtropical regions. Long-term management regimes (e.g. stocking, weed control, thinning, fertiliser application and fire management) may also influence accumulation of soil C. Accumulation is maximised by maintaining longer (20–50 years) forest rotations. Furthermore, inclusion of litter in calculations reversed the observed average decrease in soil C, so that amount of C in soil and litter layer was greater than under preceding pasture. # 2002 Elsevier Science B.V. All rights reserved.
Soil organic carbon (SOC) makes up a significant portion of the worlds terrestrial carbon stocks, and changes in land-use and land cover are changing soil carbon stocks. This study investigated the effects on soil organic carbon and some other soil properties of afforestation efforts using 15-year-old Pinus nigra Arn. Subsp. nigra (Black Pine) and Cedrus libani A. Rich (Lebanon cedar) on bare land in the semi-arid Nigde Akkaya dam watershed for erosion control and green belt creation. Soil samples were collected from three land use types (Black Pine planted, Lebanon cedar planted area and bare land) at two soil depths (0–10 cm and 10–20 cm) and replicated three times. Among the soil properties substantially affected by the change in land cover are soil organic carbon, bulk density, particle density, water holding capacity and total porosity. Generally, soil organic carbon was observed to increase after afforestation. Soil organic carbon (SOC) values were 1.09% and 1.13% in Black Pine and the Cedar area, respectively. These values were significantly higher than the values for the bare land soils (0.54%). For all types of land use, the amount of SOC in the soils decreased with depth. The amount of carbon sequestrated in Black Pine, Cedar and bare land sites at depths of 0–10 cm and 10–20 cm were 18.20 t/ha and 16.33 t/ha, 23.54 t/ha and 12.38 t/ha and 11.2 t/ha and 7.22 t/ha, respectively. The bulk density values obtained from the 0–10 cm layer soils in the afforested lands (1.53 g/cm3 for Black Pine and 1.58 g/cm3 for Cedar) were different from and lower than those in bare land (1.75 g/cm3). Afforestation efforts led to an increase in water holding capacity (WHC) of the soil. Total porosity (TP) of the 0–10 cm layer soils increased after afforestation. This study indicated that on degraded land in a semiarid region, afforestation increased soil carbon sequestration, improved some soil properties and reduced erosion over a 15-year period.
Changes in land use and vegetation cover affect various soil properties, including the soil organic carbon (SOC) pool and the transfer of atmospheric CO2 to terrestrial landscapes. In natural or quasi-natural conditions a reduction in biomass increases the risk of erosion, and can reduce the stored soil organic matter content. This can cause (i) consolidation of low levels of organic carbon stored in the soil; (ii) reduction in the levels of organic carbon because of the onset of erosion processes; and (iii) differing rates of recovery of the soil in response to environmental factors including precipitation, which is a principal agent of indirect recharge of soil organic matter.Few comparable studies have analyzed the reduction of SOC because of erosion, and assessed how this contributes to the loss of soil as vegetation cover decreases. This is particularly the case in semiarid Mediterranean environments, where erosion is one of the main causes of soil degradation.This study presents the results of an experiment carried out along a pluviometric gradient from humid to semiarid Mediterranean conditions, in southern Spain. The study involved two soil depths at five field sites having similar lithology, slope and aspect, but differ in vegetation cover and composition related to their location along the gradient. We used soil cation exchange capacity (CEC) as an indicator of soil degradation.The results showed that: a) SOC decreased with decreasing rainfall; b) SOC is greater at the soil surface than at depth; c) CEC is a good indicator of the degradation of soil surface formations, as it is directly related to the SOC storage capacity; and d) the so-called “Mediterranean mountain” landscape, with sparse and mixed vegetation composed of scrubland and woodland species, is a good organic carbon sink with direct implications in relation to climate change.
Several methods are used to correct total soil carbon data in response to land use or management changes inherently coupled with concomitant alteration to bulk density (BD). However, a rigorous evaluation of correction methods has not been conducted. We compared original, maximum, and minimum equivalent soil mass (ESM) corrections to the fixed depth (FD) method and direct C concentrations. In a simulation exercise of a tillage event that decreased BD without change in total C concentration to a depth of 0.3 m, the original and maximum ESM methods estimated changes in total C storage of −0.34 to 0.54 Mg C ha−1, well within the range of field soil C variability. In contrast, the minimum ESM method estimated changes ranging from −1.19 to 1.01 Mg C ha−1. In a field experiment on reduced and intensive tillage, soil C changes (0–0.18 m) were measured from May to August 2006. The maximum ESM method generally overestimated soil C changes by −0.16 to 0.60 Mg C ha−1 and the minimum ESM method underestimated them by −2.67 to 0.23 Mg C ha−1 compared to the original ESM method. Field-scale soil C changes (0–0.15 m) were also measured from August 2003 to June 2005 and decreased by an unrealistic 6.64 Mg C ha−1 over the first 6 months after tillage when the FD method was used. In contrast, the effect of tillage on soil C could be reasonably estimated by directly comparing changes in C concentration. In a compacted agricultural soil, we found more errors in simulated C differences when using the maximum than the minimum ESM method. Regardless of the direction of BD changes, the minimum ESM method was a better choice than the maximum ESM method in native and restored grassland systems where soil C concentrations decreased through the soil profile. We conclude that (1) the FD method is often not suitable and might be less accurate than direct C concentration measurements, and (2) the maximum/minimum ESM method can be accurate depending on the conditions (e.g., increasing or decreasing BD, systems conversion type), but (3) that the original ESM method is optimal for detecting soil C changes due to land use changes or management effects.
Lebanon cedar (Cedrus libani A. Rich.) is significant from the historical, cultural, aesthetic, scientific and economic perspectives. It is presently found primarily in the Taurus Mountains of Turkey with extensive and magnificent forests. Historical records also indicate extensive and splendid forests of it in Syria and Lebanon. However, heavy cutting, burning and goat grazing for the past 5000 years have left only small populations in these countries. Although the same disturbances have continued in Anatolia (Asia Minor), the almost inaccessible topography of the Taurus Mountains has prevented Lebanon cedar from being extirpated.
When agricultural land is no longer used for cultivation and allowed to revert to natural vegetation or replanted to perennial vegetation, soil organic carbon can accumulate. This accumulation process essentially reverses some of the effects responsible for soil organic carbon losses from when the land was converted from perennial vegetation. We discuss the essential elements of what is known about soil organic matter dynamics that may result in enhanced soil carbon sequestration with changes in land-use and soil management. We review literature that reports changes in soil organic carbon after changes in land-use that favour carbon accumulation. This data summary provides a guide to approximate rates of SOC sequestration that are possible with management, and indicates the relative importance of some factors that influence the rates of organic carbon sequestration in soil. There is a large variation in the length of time for and the rate at which carbon may accumulate in soil, related to the productivity of the recovering vegetation, physical and biological conditions in the soil, and the past history of soil organic carbon inputs and physical disturbance. Maximum rates of C accumulation during the early aggrading stage of perennial vegetation growth, while substantial, are usually much less than 100 g C m−2 y−1. Average rates of accumulation are similar for forest or grassland establishment: 33.8 g C m−2 y−1 and 33.2 g C m−2 y−1, respectively. These observed rates of soil organic C accumulation, when combined with the small amount of land area involved, are insufficient to account for a significant fraction of the missing C in the global carbon cycle as accumulating in the soils of formerly agricultural land.
A published meta-analysis of worldwide data showed soil carbon decreasing following land use change from pasture to conifer
plantation. A paired site (a native pasture with Themeda triandra dominant, and an adjacent Pinus radiata plantation planted onto the pasture 16years ago) was set up as a case study to assess the soil carbon reduction and the
possible reason for the reduction under pine, including the change in fine root (diameter <2mm) dynamics (production and
mortality). Soil analysis confirmed that soil carbon and nitrogen stocks to 100cm under the plantation were significantly
less than under the pasture by 20 and 15%, respectively. A 36% greater mass of fine root was found in the soil under the pasture
than under the plantation and the length of fine root was about nine times greater in the pasture. Much less fine root length
was produced and roots died more slowly under the plantation than under the pasture based on observations of fine root dynamics
in minirhizotrons. The annual inputs of fine root litter to the top 100cm soil, estimated from soil coring and minirhizotron
observations, were 6.3Mg dry matter ha−1 year−1 (containing 2.7Mg C and 38.9kg N) under the plantation, and 9.7Mg ha−1 year−1 (containing 3.6Mg C and 81.4kg N) under the pasture. The reduced amount of carbon, following afforestation of the pasture,
in each depth-layer of the soil profile correlated with the lower length of dead fine roots in the layer under the plantation
compared with the pasture. This correlation was consistent with the hypothesis that the soil carbon reduction after land use
change from pasture to conifer plantation might be related to change of fine root dynamics, at least in part.
There is a growing interest in using soil microbial parameters as indicators of soil quality changes after revegetation of disturbed soils. This study investigated the changes in different soil microbial parameters as well as physico-chemical parameters as affected by vegetation rehabilitation of soil in the Loess plateau of China subjected to natural succession after enclosure. The results showed that the soil nutrients tend to be concentrated in the soil surface layer, especially the soil organic C, total N and alkali extractable N with soil organic C being doubled (up to 20 g kg−1) after 50 years of revegetation. Soil enzyme activities and microbial biomass C (Cmic) and N (Nmic) increased with rehabilitation time up to 23 years. After 23 years, soil Cmic and Nmic and enzyme activities remained stable. Enzyme activities increased rapidly during the early stage of revegetation, about 15–20 years after enclosure. Soil Cmic and Nmic also increased about 20% faster up to 23 years since enclosure in the 0–20-cm soil layer. Soil basal respiration (BR) in the 23 years site was higher than in other sites, indicating high microbial activity in this site. These findings demonstrated significant impacts of natural vegetation succession in overgrazed grassland on the properties of the surface soils, including the soil nutrients, organic matter, soil microbial biomass, respiration, and enzyme activities.
The increase in atmospheric concentration of CO2 by 31% since 1750 from fossil fuel combustion and land use change necessitates identification of strategies for mitigating the threat of the attendant global warming. Since the industrial revolution, global emissions of carbon (C) are estimated at 270±30 Pg (Pg=petagram=1015 g=1 billion ton) due to fossil fuel combustion and 136±55 Pg due to land use change and soil cultivation. Emissions due to land use change include those by deforestation, biomass burning, conversion of natural to agricultural ecosystems, drainage of wetlands and soil cultivation. Depletion of soil organic C (SOC) pool have contributed 78±12 Pg of C to the atmosphere. Some cultivated soils have lost one-half to two-thirds of the original SOC pool with a cumulative loss of 30–40 Mg C/ha (Mg=megagram=106 g=1 ton). The depletion of soil C is accentuated by soil degradation and exacerbated by land misuse and soil mismanagement. Thus, adoption of a restorative land use and recommended management practices (RMPs) on agricultural soils can reduce the rate of enrichment of atmospheric CO2 while having positive impacts on food security, agro-industries, water quality and the environment. A considerable part of the depleted SOC pool can be restored through conversion of marginal lands into restorative land uses, adoption of conservation tillage with cover crops and crop residue mulch, nutrient cycling including the use of compost and manure, and other systems of sustainable management of soil and water resources. Measured rates of soil C sequestration through adoption of RMPs range from 50 to 1000 kg/ha/year. The global potential of SOC sequestration through these practices is 0.9±0.3 Pg C/year, which may offset one-fourth to one-third of the annual increase in atmospheric CO2 estimated at 3.3 Pg C/year. The cumulative potential of soil C sequestration over 25–50 years is 30–60 Pg. The soil C sequestration is a truly win–win strategy. It restores degraded soils, enhances biomass production, purifies surface and ground waters, and reduces the rate of enrichment of atmospheric CO2 by offsetting emissions due to fossil fuel.
Compared to annual crops, the use of deep-rooted vegetation, such as perennial grasses, in agricultural systems can increase soil organic C (SOC) storage deep within the soil profile. However, this potential increase could be adversely influenced by physical limitations in the soil profile. Tall fescue (Lolium arundinaceum Schreb.) was grown for 7 years after a long-term tillage experiment on a fine sandy loam (Orthic Podzol) in Prince Edward Island which had naturally compacted subsoil. Soil samples from the 0–60 cm soil depth (divided into five depth increments) were collected periodically from 2000 to 2007 to evaluate the potential for tall fescue to increase SOC and total N (TN) storage and depth distribution in the soil profile, especially in subsurface soil layers. Light fraction C (LF-C) and particulate organic matter C (POM-C) were also evaluated as indicators of SOC change in the soil profile. Annual tall fescue biomass yield (>7 Mg dry matter ha−1) was above regional norms, but rooting depth (70–90 cm) was relatively shallow. Comparison of the 2000 and 2007 data showed that tall fescue increased SOC and TN in the 0–10 and 40–60 cm soil depths. Over the 0–60 cm soil depth, SOC content increased by 23% and TN by 34%. Use of the equivalent soil mass approach, to adjust for soil bulk density increases over the 7-year period, reduced the SOC gain to 17% (increase of 12.8 Mg C ha−1). This SOC increase corresponded with standard decomposition calculations based on plant biomass inputs. Both LF-C and POM-C indicated that tall fescue increased SOC down the soil profile. This research demonstrates the important role that plant roots which play in SOC storage deep within the soil profile, even when soil profile conditions may adversely influence rooting depth.
Afforestation of degraded pastures can potentially enhance carbon sequestration, but little is known about the effects of eucalyptus plantations on soil organic matter (SOM) fractions. We used density and particle size SOM fractionations to evaluate changes in SOM for a chronosequence of eucalyptus plantations established on degraded pastures in two contrasting regions in southeastern Brazil. Declines in the content of soil C derived from the pasture (C4 photosynthetic pathway) and the accumulation of that derived from the eucalyptus (C3 photosynthetic pathway) were followed through 13C natural abundance of the SOM. The two study areas were in the Rio Doce River Valley, Minas Gerais State, namely: 1, Belo Oriente (BO, a region with lower elevation, higher mean annual temperature, lower forest productivities and dominated by clayey Typic Haplustoxs); 2, Virginópolis (VG, a region of higher elevation, higher forest productivities and dominated by clayey Rhodic Ustoxs). In the BO region the chronosequence included 0, 4.2, 13.2, 22.2, 32.0 and 34.2 years of eucalyptus cultivation and in the VG region soils were cultivated with eucalyptus for 0, 8.2, 19.2, 29.2 and 33.2 years. The accumulated cultivation time corresponds to about five rotations. In both regions the initial soil condition was represented by a site that was still under pasture. Soil samples collected at 0–10 and 10–20 cm depths were analyzed for: total organic carbon (TOC); C in the fulvic (FAF), humic (HAF) and humin (HF) fractions; C in the free (FLF) and occluded (OLF) light fractions; C associated with the heavy fractions, namely, the sand (SF), silt plus clay (S + CF) and clay (CF) fractions; and C in the microbial biomass (MB). Carbon stocks of virtually all SOM fractions were about twice as high in the VG region than in the BO region. Eucalyptus cultivation in the BO region increased C stocks in all SOM fractions, except for the MB fraction that was not altered and the SF fraction that declined with time of eucalyptus cultivation. Increases in TOC, FAF and HF organic C fractions were observed in the VG region. Mean annual accumulations across the entire cultivation period in the 0–10 cm soil layer showed virtually no difference averaging 0.22 Mg C ha−1 year−1 for the BO region and 0.23 Mg C ha−1 year−1 for the VG region. However, gains of TOC peaked by the end of the third rotation in the BO region and the second rotation in the VG region, so the TOC accumulation rate during the respective aggrading periods would correspond to 0.35 and 0.57 Mg C ha−1 year−1. There was no clear evidence that the more labile, fast cycling SOM fractions were more sensitive indicators of the impact of eucalyptus cultivation in the BO region, whereas in the VG region the FLF and OLF were more sensitive to the land use change than TOC.
Changes in the carbon stocks of stem biomass, organic layers and the upper 50 cm of the mineral soil during succession and afforestation of spruce ( Picea abies ) on former grassland were examined along six chronosequences in Thuringia and the Alps. Three chronosequences were established on calcareous and three on acidic bedrocks. Stand elevation and mean annual precipitation of the chronosequences were different. Maximum stand age was 93 years on acid and 112 years on calcareous bedrocks. Stem biomass increased with stand age and reached values of 250–400 t C ha ⁻¹ in the oldest successional stands. On acidic bedrocks, the organic layers accumulated linearly during forest succession at a rate of 0.34 t C ha ⁻¹ yr ⁻¹ . On calcareous bedrocks, a maximum carbon stock in the humus layers was reached at an age of 60 years.
Total carbon stocks in stem biomass, organic layers and the mineral soil increased during forest development from 75 t C ha ⁻¹ in the meadows to 350 t C ha ⁻¹ in the oldest successional forest stands (2.75 t C ha ⁻¹ yr ⁻¹ ). Carbon sequestration occurred in stem biomass and in the organic layers (0.34 t C ha ⁻¹ yr ⁻¹ on acid bedrock), while mineral soil carbon stocks declined.
Mineral soil carbon stocks were larger in areas with higher precipitation. During forest succession, mineral soil carbon stocks of the upper 50 cm decreased until they reached approximately 80% of the meadow level and increased slightly thereafter. Carbon dynamics in soil layers were examined by a process model. Results showed that sustained input of meadow fine roots is the factor, which most likely reduces carbon losses in the upper 10 cm. Carbon losses in 10–20 cm depth were lower on acidic than on calcareous bedrocks. In this depth, continuous dissolved organic carbon inputs and low soil respiration rates could promote carbon sequestration following initial carbon loss.
At least 80 years are necessary to regain former stock levels in the mineral soil. Despite the comparatively larger amount of carbon stored in the regrowing vegetation, afforestation projects under the Kyoto protocol should also aim at the preservation or increase of carbon in the mineral soil regarding its greater stability of compared with stocks in biomass and humus layers. If grassland afforestation is planned, suitable management options and a sufficient rotation length should be chosen to achieve these objectives. Maintenance of grass cover reduces the initial loss.
Land use changes represent one of the most important components of global environmental change. In most European countries, the transformed economies and social conditions of previous decades have had consequences in terms of agriculture intensification, industrialization and migration of people from the rural areas. As a consequence, areas of marginal agriculture were abandoned leading to secondary successions. This research studied the effects of the natural recovery of abandoned lands on carbon pools using a chronosequence approach of mixed ash (Fraxinus excelsior L.) and sycamore ( Acer pseudoplatanus L.) stands in the Eastern Italian Prealps. A series of five formerly cultivated sites spanning a range of 40 - 75 years since agricultural abandonment and a meadow were selected. The dominant sink for the atmospheric CO 2 within these secondary forests seems to be live wood while the soil played a much smaller role. The ecosystem carbon stock increased at a mean rate of 1.18 Mg C ha(-1) y(-1) during the chronosequence. However, a difference in the carbon accumulation in the different pools was detected.
This paper reviews the effects of past forest management on carbon stocks in the United States, and the challenges for managing forest carbon resources in the 21st century. Forests in the United States were in approximate carbon balance with the atmosphere from 1600-1800. Utilization and land clearing caused a large pulse of forest carbon emissions during the 19th century, followed by regrowth and net forest carbon sequestration in the 20th century. Recent data and knowledge of the general behavior of forests after disturbance suggest that the rate of forest carbon sequestration is declining. A goal of an additional 100 to 200 Tg C/yr of forest carbon sequestration is achievable, but would require investment in inventory and monitoring, development of technology and practices, and assistance for land managers.
Soil organic matter (SOM) is the largest C stock of the continental biosphere with 1550Pg. The size of C reservoir in the soil and environmental concerns on climate change have recently attracted the attention of scientist and politicians on C sequestration as an effective strategy to tackle greenhouse gas (GHG) emissions. It has been estimated that the potential for C storage in world cropland is relevant (about 0.6-1.2PgCy(-1)). However, there are several constraints of C sequestration that raise concern about its effectiveness as a strategy to offset climate change. C sequestration is finite in quantity and time, reversible, and can be further decreased by socio-economic restrictions. Given these limitations, C sequestration can play only a minor role in the reduction of emissions (2-5% of total GHG emission under the highest emission scenarios). Yet, C sequestration is still attractive for two main reasons: it is likely to be particularly effective in reducing atmospheric CO2 levels in the first 20-30yr of its implementation and presents ancillary benefits for environment and sustainability that make it a real win-win strategy. These beneficial implications are discussed in this paper with emphasis on the need of C sequestration not only to offset climatic changes, but also for the equilibria of the environment and for the sustainability of agriculture and of entire human society.
This paper serves two purposes: it provides a summarized scientific history of carbon sequestration in relation to the soil-plant system and gives a commentary on organic wastes and SOC sequestration. The concept of soil organic carbon (SOC) sequestration has its roots in: (i) the experimental work of Lundegårdh, particularly his in situ measurements of CO2 fluxes at the soil-plant interface (1924, 1927, 1930); (ii) the first estimates of SOC stocks at the global level made by Waksman [Waksman, S.A., 1938. Humus. Origin, Chemical Composition and Importance in Nature, second ed. revised. Williams and Wilkins, Baltimore, p. 526] and Rubey [Rubey, W.W., 1951. Geologic history of sea water. Bulletin of the Geological Society of America 62, 1111-1148]; (iii) the need for models dealing with soil organic matter (SOM) or SOC dynamics beginning with a conceptual SOM model by De Saussure (1780-1796) followed by the mathematical models of Jenny [Jenny, H., 1941. Factors of Soil Formation: a System of Quantitative Pedology. Dover Publications, New York, p. 288], Hénin and Dupuis [Hénin, S., Dupuis, M., 1945. Essai de bilan de la matière organique. Annales d'Agronomie 15, 17-29] and more recently the RothC [Jenkinson, D.S., Rayner, J.H., 1977. The turnover of soil organic matter in some of the Rothamsted classical experiments. Soil Science 123 (5), 298-305] and Century [Parton, W.J., Schimel, D.S., Cole, C.V., Ojima, D.S., 1987. Analysis of factors controlling soil organic matter levels in great plains grasslands. Soil Science Society of America Journal 51 (5), 1173-1179] models. The establishment of a soil C sequestration balance is not straightforward and depends greatly on the origin and the composition of organic matter that is to be returned to the system. Wastes, which are important sources of organic carbon for soils, are taken as an example. For these organic materials the following factors have to be considered: the presence or absence of fossil C, the potential of direct and indirect emissions of non-CO2 greenhouse gases (CH4 and N2O) following application and the agro-system which is being used as a comparative reference.
Sedir ormanlarının yayılıs¸ gösterdiği alanlar ve yakın çevresinin genel ekolojik özellikleri ile sedir tohum transfer rejyonlaması (General ecological properties of natural occurrence areas of cedar (Cedrus libani A. Rich) forests and regioning of seed transfer of cedar in Turkey)
- I Atalay
Atalay, I. (1987). Sedir ormanlarının yayılıs¸ gösterdiği alanlar ve yakın çevresinin genel
ekolojik özellikleri ile sedir tohum transfer rejyonlaması (General ecological properties
of natural occurrence areas of cedar (Cedrus libani A. Rich) forests and regioning of
seed transfer of cedar in Turkey). Orman Genel Müdürlüğü yayını (Ankara) 663 (in
Turkish with English Summary).
Arkeolojik arastırmaların ışıgı altında Iç Anadolu stebi (La steppe d’Anatolie centrale a`la lamie`re des recherches arche´ologiques). İ.Ü
- B Aytug
Aytug, B. (1970). Arkeolojik arastırmaların ışıgı altında Iç Anadolu stebi (La steppe
d'Anatolie centrale a`la lamie`re des recherches arche´ologiques). İ.Ü.Orman Fakültesi
Dergisi A 20 (1), 127-143.
Ecology and Silviculture of Cedar of Lebanon (Cedrus libani A. Rich.) and Conservation of its Natural Forests
- M Boydak
Boydak, M. (1996). Ecology and Silviculture of Cedar of Lebanon (Cedrus libani A. Rich.)
and Conservation of its Natural Forests. Publication 12, Ministry of Forestry, Ankara.
Karaisalı Kireçtası’nın (Kalfalar Köyü-Kadirli) Mermer Olarak Kullanılabilme Olanaklarının Arastırılması (Yüksek Lisans Tezi) (pp
- B Bulut
Bulut, B. (1998). Karaisalı Kireçtası'nın (Kalfalar Köyü-Kadirli) Mermer Olarak
Kullanılabilme Olanaklarının Arastırılması (Yüksek Lisans Tezi) (pp. 27-69). Çukurova
Üniversitesi, Fen Bilimleri Enstitüsü, FBE.97.YL.151.
European Commission, Eurostat
- Ec
EC. (2009). European Commission, Eurostat, 2009. LUCAS 2009 technical reference
document C1. Instruction for surveyors. http: //ec. europa.eu/ euros tat/documents/2
05002 /6786 255/L UCAS2 015-C 1-Instructions-20150 227.pdf. Accessed 08.02.2022.
Hızlı gelişen türlerle ilgili rapor (report on fast growing tree species)
- T Çalışkan
Çalışkan, T. (1998). Hızlı gelişen türlerle ilgili rapor (report on fast growing tree species). In:
Proceedings of Workshop (Hızlı gelişen türlerle yapılan ağaçlandırma çalışmalarının
değerlendirilmesi ve yapılacak çalışmalar, November 8-9, 1998, Ankara). Orman
BakanlıĞI Yayını (Ankara) 83, 109-130
Some petrographic, soil and vegetative characteristics of karst forest ecosystems; Kahramanmaras-Andirin Sarimsak Mountain example
- Y Vermez
- T Dindaroglu
- T Rizaoglu
Vermez, Y., Dindaroglu, T. & Rizaoglu, T. (2018). Some petrographic, soil and vegetative
characteristics of karst forest ecosystems; Kahramanmaras-Andirin Sarimsak Mountain
example. KSU Journal of Agrıculture and Nature, 21(1), 32-43.