| 1. |
- Bansal, Sheel, et al.
(författare)
-
Practical Guide to Measuring Wetland Carbon Pools and Fluxes
- 2023
-
Ingår i: Wetlands (Wilmington, N.C.). - : SPRINGER. - 0277-5212 .- 1943-6246. ; 43:8
-
Forskningsöversikt (refereegranskat)abstract
- Wetlands cover a small portion of the world, but have disproportionate influence on global carbon (C) sequestration, carbon dioxide and methane emissions, and aquatic C fluxes. However, the underlying biogeochemical processes that affect wetland C pools and fluxes are complex and dynamic, making measurements of wetland C challenging. Over decades of research, many observational, experimental, and analytical approaches have been developed to understand and quantify pools and fluxes of wetland C. Sampling approaches range in their representation of wetland C from short to long timeframes and local to landscape spatial scales. This review summarizes common and cutting-edge methodological approaches for quantifying wetland C pools and fluxes. We first define each of the major C pools and fluxes and provide rationale for their importance to wetland C dynamics. For each approach, we clarify what component of wetland C is measured and its spatial and temporal representativeness and constraints. We describe practical considerations for each approach, such as where and when an approach is typically used, who can conduct the measurements (expertise, training requirements), and how approaches are conducted, including considerations on equipment complexity and costs. Finally, we review key covariates and ancillary measurements that enhance the interpretation of findings and facilitate model development. The protocols that we describe to measure soil, water, vegetation, and gases are also relevant for related disciplines such as ecology. Improved quality and consistency of data collection and reporting across studies will help reduce global uncertainties and develop management strategies to use wetlands as nature-based climate solutions.
|
|
| 2. |
- Lin, Yan-Shih, et al.
(författare)
-
Optimal stomatal behaviour around the world
- 2015
-
Ingår i: Nature Climate Change. - : Springer Science and Business Media LLC. - 1758-678X .- 1758-6798. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- Stomatal conductance (gs) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of gs in predictions of global water and carbon cycle changes, a globalscale database and an associated globally applicable model of gs that allow predictions of stomatal behaviour are lacking. Here,we present a database of globally distributed gs obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model1 and the leaf and wood economics spectrum2,3.We also demonstrate a global relationship with climate. These findings provide a robust theoretical framework for understanding and predicting the behaviour of gs across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate.
|
|
| 3. |
- Lin, Yan-Shih, et al.
(författare)
-
Optimal stomatal behaviour around the world
- 2015
-
Ingår i: Nature Climate Change. - 1758-6798 .- 1758-678X. ; 5:5, s. 459-464
-
Tidskriftsartikel (refereegranskat)abstract
- Stomatal conductance (g(s)) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of g(s) in predictions of global water and carbon cycle changes, a global-scale database and an associated globally applicable model of g(s) that allow predictions of stomatal behaviour are lacking. Here, we present a database of globally distributed g(s) obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model(1) and the leaf and wood economics spectrum(2,3). We also demonstrate a global relationship with climate. These findin g(s) provide a robust theoretical framework for understanding and predicting the behaviour of g(s) across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate.
|
|
| 4. |
- Stenberg, Elin, et al.
(författare)
-
How four typical Swedish production systems for lambs affect sensory attributes of the meat
- 2018
-
Ingår i: Proceedings 27th European Grassland Federation General Meeting. ; , s. 780-782
-
Konferensbidrag (refereegranskat)abstract
- The aim of this study was to evaluate the effect of the four most typical producdon systems for Swedish lamb on sensory atrributes of meat, including appearance, texture, taste and flavour using an analytical panel. The experiment included four production treatments for weaned intact male lambs: (1) indoor fed with grass and clover silage ad libitum and 0.8 kg concentrate daily per lamb; (2) grazing on cultivated pasture with; or (3) without 0.3 kg concentrate supplementation daily per lamb; and (4) grazing on semi natura! pasture; eight lambs per producdon treatment were used. Feed radons, pasture height and live weight of the lambs were recorded. At slaughter, live weight, carcass conformation, fatness, pH and temperature decline in musde during 24 hoursafi:er slaughter were registered. Sensory and technological meat quality parameters were tested in cooked samples of M longissimus dorsi. Meat colour was not affected by treatment. Most sensor attributes were unaffected by producdon system hut for 'hay odour' and 'resistance to cutting; differences between the systems were manifested.
|
|
| 5. |
- Hyvonen, R., et al.
(författare)
-
The likely impact of elevated [CO2], nitrogen deposition, increased temperature and management on carbon sequestration in temperate and boreal forest ecosystems: a literature review
- 2007
-
Ingår i: New Phytologist. - Cambridge : Wiley. - 0028-646X .- 1469-8137. ; 173:3, s. 463-480
-
Forskningsöversikt (refereegranskat)abstract
- Temperate and boreal forest ecosystems contain a large part of the carbon stored on land, in the form of both biomass and soil organic matter. Increasing atmospheric [CO2], increasing temperature, elevated nitrogen deposition and intensified management will change this C store. Well documented single-factor responses of net primary production are: higher photosynthetic rate (the main [CO2] response); increasing length of growing season (the main temperature response); and higher leaf-area index (the main N deposition and partly [CO2] response). Soil organic matter will increase with increasing litter input, although priming may decrease the soil C stock initially, but litter quality effects should be minimal (response to [CO2], N deposition, and temperature); will decrease because of increasing temperature; and will increase because of retardation of decomposition with N deposition, although the rate of decomposition of high-quality litter can be increased and that of low-quality litter decreased. Single-factor responses can be misleading because of interactions between factors, in particular those between N and other factors, and indirect effects such as increased N availability from temperature-induced decomposition. In the long term the strength of feedbacks, for example the increasing demand for N from increased growth, will dominate over short-term responses to single factors. However, management has considerable potential for controlling the C store.
|
|
| 6. |
- Gardner, A., et al.
(författare)
-
Optimal stomatal theory predicts CO2 responses of stomatal conductance in both gymnosperm and angiosperm trees
- 2022
-
Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 237:4, s. 1229-41
-
Tidskriftsartikel (refereegranskat)abstract
- Optimal stomatal theory predicts that stomata operate to maximise photosynthesis (A(net)) and minimise transpirational water loss to achieve optimal intrinsic water-use efficiency (iWUE). We tested whether this theory can predict stomatal responses to elevated atmospheric CO2 (eCO(2)), and whether it can capture differences in responsiveness among woody plant functional types (PFTs). We conducted a meta-analysis of tree studies of the effect of eCO(2) on iWUE and its components A(net) and stomatal conductance (g(s)). We compared three PFTs, using the unified stomatal optimisation (USO) model to account for confounding effects of leaf-air vapour pressure difference (D). We expected smaller g(s), but greater A(net), responses to eCO(2) in gymnosperms compared with angiosperm PFTs. We found that iWUE increased in proportion to increasing eCO(2) in all PFTs, and that increases in A(net) had stronger effects than reductions in g(s). The USO model correctly captured stomatal behaviour with eCO(2) across most datasets. The chief difference among PFTs was a lower stomatal slope parameter (g(1)) for the gymnosperm, compared with angiosperm, species. Land surface models can use the USO model to describe stomatal behaviour under changing atmospheric CO2 conditions.
|
|
| 7. |
- Stenberg, Elin, et al.
(författare)
-
How four typical Swedish production systems for lambs affect sensory attributes of the meat
- 2018
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this study was to evaluate the effect of the four most typical producdon systems for Swedish lamb on sensory atrributes of meat, including appearance, texture, taste and flavour using an analytical panel. The experiment included four production treatments for weaned intact male lambs: (1) indoor fed with grass and clover silage ad libitum and 0.8 kg concentrate daily per lamb; (2) grazing on cultivated pasture with; or (3) without 0.3 kg concentrate supplementation daily per lamb; and (4) grazing on semi natura! pasture; eight lambs per producdon treatment were used. Feed radons, pasture height and live weight of the lambs were recorded. At slaughter, live weight, carcass conformation, fatness, pH and temperature decline in musde during 24 hoursafi:er slaughter were registered. Sensory and technological meat quality parameters were tested in cooked samples of M longissimus dorsi. Meat colour was not affected by treatment. Most sensor attributes were unaffected by producdon system hut for 'hay odour' and 'resistance to cutting; differences between the systems were manifested.
|
|
| 8. |
- Ewerlöf, Sofia, et al.
(författare)
-
DN Debatt. ”Låt gräsklipparen stå – för naturens skull”
- 2023
-
Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- In an era of species extinction and climate change, we should abandon the well-trimmed lawn and let gardens grow wilder, writes Anna Persson and other researchers and landscape architects on DN Debatt.
|
|
| 9. |
- Nsabimana, Donat, 1968, et al.
(författare)
-
Soil carbon and nutrient accumulation under forest plantations in southern Rwanda
- 2008
-
Ingår i: African Journal of Environmental Science and Technology. - 1996-0786. ; 2:6, s. 142-149
-
Tidskriftsartikel (refereegranskat)abstract
- Tree and soil interactions may result in changes in soil carbon and nutrient contents. Forest plantations made up of monodominant stands of 17 different species, some native and some exotic to Rwanda, as well as a stand with mixed native tree species were investigated. Biosequential sampling was used followed by basic soil chemical analyses. Results revealed that the plantation species composition influenced the soil chemical properties. Total soil C and N, C: N ratio, available P, pH, and cation exchange capacity (CEC) differed significantly between plantation stands of different species (P < 0.001, N = 54). Increases in the levels of soil C, total N, CEC and base saturation (BS) were observed mainly in mixed native species (MNS), Polyscia fulva, Casuarina equisetifolia and Eucalyptus saligna. The pH declined slightly in soil beneath some Eucalyptus species treatments and increased in others. The high nutrient uptake by fast-growing trees and the acidic parent material were involved in the acidification process. The findings suggest that the species used in afforestation maintain soil fertility and protect the environment. It is recommended that afforestation of abandoned and less productive lands in Rwanda should utilize fast growing Eucalyptus species in combination with agroforestry and native species in order to maintain or improve soil chemical properties.
|
|
| 10. |
- Barcelo, Marta, et al.
(författare)
-
Isolation and culture of strawberry protoplasts and field evaluation of regenerated plants
- 2019
-
Ingår i: Scientia Horticulturae. - : ELSEVIER. - 0304-4238 .- 1879-1018. ; 256
-
Tidskriftsartikel (refereegranskat)abstract
- Protoplasts are an useful biotechnological tool for plant improvement In strawberry, very few studies on protoplast technology have been carried out. In this investigation, a procedure for the isolation and culture of strawberry protoplasts, cv. 'Chandler', has been developed. The effect of several factors affecting the successful isolation of protoplasts and formation of microcalli, e.g. explant source, washing procedure, hormonal composition of the culture medium and protoplast density, were evaluated. For shoot regeneration, microcalli derived from isolated protoplasts were transferred to MS medium supplemented with 0.2 mg l(-1) NAA and either 5 mg l(-1) BA or 3 mgl(-1) TDZ, obtaining a similar regeneration rate, 17%, in both media. Twenty-one independent protoclones were transferred to field conditions for agronomic evaluation. Significant alterations in the growth habit, density of foliage, leaf color and leaf morphology were detected in some lines. Fruit yield was significantly reduced in 15 out of the 21 protoclones evaluated due to a reduction in fruit weight and/or the number of fruits. Ploidy level was unaffected in a sample of 6 lines selected at random; however, a study of genetic stability by using 10 EST-SSR markers showed genetic alterations in all the lines analyzed. Despite the high rate of somaclonal variation detected in the protoclones, some of the lines displayed an agronomical behavior similar to control plants, indicating that this protocol could be useful for genetic improvement in this species.
|
|
