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The shea tree, Vitellaria paradoxa, shields people, crops and livestock in West African parkland agroforestry systems from climate variability. Accurate estimates of accumulated biomass of such key species may support ways to secure financial incentives within global climate policies. In this quest, variation in allometric relations used for biomass (carbon stock) estimates on the basis of stem diameter matters, but parameters a and b of the standard format (AGB = a Db; AGB = aboveground biomass, D = stem diameter) are correlated and are directly related to tree shapes. Functional branch analysis (FBA) allows non-destructive derivation of allometrics. For Koutiala and Yanfolila shea populations empirical branching parameters were scale-independent, matching FBA assumptions. Allometry (AGB = 169 (D/20)2.64 and AGB = 146 (D/20)2.65, kg tree−1) implied 22%, 16% and 11% larger vegetative aboveground biomass in Koutiala than in Yanfolila at stem diameters (D) of 10, 20 and 32 cm, respectively. Below-ground biomass predictions (BGBi = 8.73 (Di/10)2.35 and BGBi = 8.16 (Di/10)2.38, kg per proximal root) differed − 6% and − 15% for root diameters Di of 10 and 32 cm, respectively. On a dry weight basis, the shoot:root ratio was 2.7 and 2.9, respectively for the two sites. Stand-level above-and below-ground carbon stocks in Koutiala (2.16 ± 0.44 and 0.8 ± 0.15 Mg C ha−1) were not significantly different from those in Yanfolila (3.21 ± 0.60 and 1.26 ± 0.21 Mg C ha−1), respectively. Further research is required to include (potential) fruit production to the plant architectural model.

Efforts to understand why some species become successful invaders and why some habitats are more at risk from invasive species is an important research focus in invasion ecology. With current global climate change, evaluation of the effects of shade and drought on cohabiting native and invasive species from extreme ecosystems is especially important. Acacia tortilis subsp. raddiana is a tree taxon native to arid African deserts. Prosopis glandulosa, native to the southwestern United States and Mexico, is invading African arid and semiarid regions that are habitat for A. t. subsp. raddiana. The aim of this study was to evaluate and compare the tolerance and responses of the seedlings of these two tree species to shade, water stress and their interactions. We measured and recorded growth rates and morphological, biochemical and physiological plant traits under two radiation and two water treatments in greenhouse conditions. Radiation intensity was a stronger driver of the performance of both species than water availability. Beyond the independent effects of shade and drought, the interactions of these factors yielded synergistic effects on seedlings of both tree species, affecting key plant traits. The seedlings of A. t. subsp. raddiana were able to implement important shifts in key functional traits in response to altering abiotic stress conditions, behaving as a stress-tolerant species that is well-adapted to the habitat it occupies in hot arid African deserts. In contrast, the fast-growing seedlings of P. glandulosa were stress-avoiding. The alien P. glandulosa seedlings were highly sensitive to water and shade stress. Moreover, they were particularly sensitive to drought in shade conditions. However, although alien P. glandulosa seedlings were exposed to high stress levels, they were able to avoid permanent damage to their photosynthetic apparatus by mechanisms such as increasing energy dissipation by heat emission and by adjusting the relative allocation of resources to above- and below-ground structures. Our results are useful for conservation planning and restoration of invaded hyperarid ecosystems.

Wetlands serve important ecosystem functions such as carbon sequestration but are often affected by disturbances like urban development, agriculture, and road building. For wetlands created to mitigate losses, it is important that the ecosystem functions successfully replicate those of natural wetlands. Created wetlands have frequently not provided these functions due to issues including low organic carbon (OC), high soil bulk density (BD), lost topsoil, incorrect hydrology, and failure of targeted vegetation establishment. Organic matter (OM) amendments help created wetlands attain these functions quicker, but, their long-term effects are seldom reported. This research's purpose was to measure the long-term effects of treatments at a sandy tidal freshwater wetland created in 2003 (WWE) and a fine-textured, non-tidal wetland created in 2002 (CCW). We tested OM treatments, topsoil amendment, and microtopography effects on soil and vegetation properties at WWE and OM treatments at CCW. Pedogenic changes in soil morphology, physical and chemical properties were detected by comparing data to previous studies at these sites. At both sites, litter and biomass parameters were measured to estimate total mass C. Herbaceous biomass was measured at WWE. At WWE, no long-term OM treatment effects from 78 or 156 Mg ha-1 were observed. Soils in pits had higher OC, lower BD, and lower chroma than soils on mounds. Sandy and loamy HSFI's developed at WWE within four years, but there were fewer sandy indicators after 12 years. Loamy HSFI's were lost at CCW from 2003 to 2016. Plots at WWE that were amended with topsoil had higher soil mass C than the sandy soil due to a finer texture, but total mass C did not vary. At CCW, long-term OM treatment effects were observed, including lower BD, higher soil mass C, and higher tree mass C with increasing compost rates up to 224 Mg ha-1. Overall, the ideal compost loading rate for constructed wetlands varied with wetland type and mitigation goals. Compost rates of 112 Mg ha-1 are sufficient for short term establishment of wetland vegetation and hydric soil properties, but higher rates near 224 Mg ha-1 may be required for effects that last over 10 years. Ph. D.

Eucalyptus stands in semi-arid areas may contribute to enhance carbon (C) stocks in both biomass and soil. However, the limited information available is mainly focused on short-rotation plantations. In this study, the above- and below-ground C pools in five 50-year-old Eucalyptus camaldulensis Dehnh. stands planted on Miocenic evaporitic deposits in Sicily, Italy, with a xeric and thermic pedoclimate, were measured. Above-ground biomass was determined by partitioning and weighing branches, stem and leaves. Below-ground C pools included the determination of litter, root biomass, and soil organic and inorganic C. In terms of the above-ground biomass, the E. camaldulensis stand accumulated on average 116 Mg ha-1 corresponding to 55 Mg C ha-1. Below-ground biomass consisted mainly of larger roots, followed by fine and medium roots (33 Mg ha-1 corresponding to 14 Mg C ha-1). Litter accumulation on the soil surface accounted for 13 Mg ha-1 corresponding to 5 Mg C ha-1. The amount of C stored in soil was 554 Mg C ha-1, of which 75% was in organic form. Although E. camaldulensis is planted extensively throughout the Southern Hemisphere and tropics where it is managed over short rotations (c. 2–4 years), the results obtained from this study make this species important in terms of future afforestation planning for longer rotations due to its potential to sequester C, particularly in the below-ground components.

Mangroves play an important role in the storage of carbon (C) and nitrogen (N) within estuarine systems, yet are being lost at an alarming rate throughout the tropics. In contrast, temperate mangroves have increased in area at many locations in recent decades. Field surveys, sediment sampling, allometry, and C and N analysis were used to determine total C and N stocks in five temperate Avicennia marina subsp. australasica forests in New Zealand. This is the first study developing allometric functions to estimate root biomass C and N stocks for A. marina. A. marina forests stored 117.1 ± 16.8 t C ha-1 and 15.4 ± 1.0 t N ha-1 in above and below ground biomass and sediment to 100 cm depth. Below ground biomass and sediment C and N stocks contributed 88 ± 3% and 99% ± 0.4% to total C and N stocks, respectively, emphasising the importance of below ground biomass and sediment in mangrove ecosystems. The results of this study can be used to inform management decisions for estuarine and coastal ecosystems, currently undergoing rapid changes in mangrove area.

Certainty over warming-induced biomass accumulation is essential for addressing climate change. However, no previous meta-analysis has investigated this accumulation across the whole of China, also unclear are the differences between herbaceous and woody species and across plant phylogeny, which are critical for corresponding re-vegetation. We extracted data from 90 field-based experiments to reveal general patterns and driving factors of biomass responses all over China. Based on traditional meta-analyses, a warmer temperature significantly increased above- (10.8%) and below-ground (14.2%) biomass accumulation. With increasing warming duration (WarmD) and plant clade age, both above-ground and below-ground biomass showed significant increases. However, for herbaceous versus woody plants, and the whole community versus its dominant species, responses were not always constant, the combined synergies would affect accumulative response patterns. When considering WarmD as a weight, decreases in total above-ground biomass response magnitude were presented, and the increase in below-ground biomass was no longer significant, notably, significant positive responses remained in tree species. However, if phylogenetic information was included in the calculations, all warming-induced plant biomass increases were not significant. Thus, it is still premature to speculate whether warming induces biomass increases in China, further long-term experiments are needed regarding phylogeny-based responses and interspecies relations, especially regarding woody plants and forests.

Restoration of Atlantic Forests is receiving increasing attention because of its role in both biodiversity conservation and carbon sequestration for global climate change mitigation. This study was carried out in an Atlantic Forest restoration project in the south-central region of Sao Paulo State - Brazil to develop allometric equations to estimate tree biomass of indigenous tree species in mixed plantations. Above and below-ground biomass (AGB and BGB, respectively), stem diameter (DBH: diameter at 1.3 m height), tree height (H: total height) and specific wood density (WD) were measured for 60 trees of 19 species. Different biomass equations (linear and nonlinear-transformed) were adjusted to estimate AGB and BGB as a function of DBH, H and WD. For estimating AGB and BGB, the linear biomass equation models were the least accurate. The transformed nonlinear biomass equation that used log DBH 2 , log H and log WD as predictor variables were the most accurate for AGB and the transformed nonlinear biomass equations that used log DBH 2 *WD as predictor variables were the most accurate for BGB. It is concluded that these adjusted equations can be used to estimate the AGB and BGB in areas of the studied project. The adjusted equations can be recommended for use elsewhere in the region for forest stands of similar age, tree size ranges, species composition and site characteristics. Keywords: Above-ground biomass, Below-ground biomass, Biomass equation, Tree allometry, Atlantic Forest, Restoration.

The distribution along the soil profile of Eucalyptus globulus root biomass was followed in a plantation in central Portugal at 1, 2 and 6 years after planting, using an excavation technique. The experimental design consisted of a control (C)and 3 treatments: application of solid fertilizers twice a year (F), irrigation without the application of fertilizers (I) and irrigation combined with liquid fertilizers (IL). Bellow- and above-ground biomass decreased as follows: IL>I>F>C. So, water stress limited growth more severely than nutrient stress. The roots rapidly colonized the top soil volume (0-20 cm depth)during the first year after planting. Fine roots biomass 6 years after planting was 2.2, 1.8 and 1.6 times higher in IL treatment than it was respectively in control, and in F and I treatments. The distribution of fine roots along the soil profile 6 years after planting was more even in IL compared to the other treatments. However, fine roots in the top soil were more concentrated along the tree rows in the irrigated treatments than in the others. The proportion of below-ground biomass relative to the total tree biomass relative to the total tree biomass and the root/shoot ratio were higher in C than in the treatments at early growth stages. This pattern was not so clear 6 years after planting, due to the increased proportion of the tap root relative to total biomass, especially in the IL treatment.

The ability to predict the spatial distribution of tree root system variables (e.g., the Root system Area (RA), the maximum root diameter, the number of roots in diameter classes, the density of fine roots, etc.) under different environmental conditions is relevant to several scientific disciplines and to engineering practice. In this work, three well known analytical models from the literature are assembled into a unique framework called the Root Distribution Model (RDM). RDM models the expected vertical and horizontal distribution of coarse and fine root system variables for mature plants growing in different environmental conditions ranging from moderately humid to arid climates. All soil and moisture dynamic parameters are physically based, which make the model straightforward to calibrate via a single tuning parameter. At this investigative stage, it is shown that the model has the flexibility to represent a broad range of situations where soil moisture may result from precipitation inputs or from water level fluctuations due to either the presence of a water course or of deep aquifers or both. Accordingly, the distribution of the sectional RA may be either positively or negatively skewed, as well as show a peculiar bi-modal structure. The model can be used to study the impact of changing scenarios affecting precipitation, aquifer and channel hydrology.