Ocean temperature controls kelp decomposition and carbon sink potential

Compelling new evidence shows that kelp production contributes an important and underappreciated flux of carbon in the ocean. Major questions remain, however, about the controls on the cycling of this organic carbon in the coastal zone, and their implications for future carbon sequestration. Here we used field experiments distributed across 28° latitude, and the entire range of two dominant kelps in the northern hemisphere, to measure decomposition rates of kelp detritus on the seafloor in relation to environmental factors. Ocean temperature was the strongest control on detritus decomposition in both species, and it was positively related to decomposition. This suggests that decomposition could accelerate with ocean warming under climate change, increasing remineralization and reducing overall kelp carbon sequestration. However, we also demonstrate the potential for high kelp-carbon storage in cooler (northern) regions, which could be targeted by climate mitigation strategies to expand blue carbon sinks.

The Production of Organic Matter from Rhizophora mucronata and Sonneratia alba at The Kajhu and Meunasah Mesjid Villages, Aceh Besar

Production and decomposition of mangrove litter could contribute organic matter and nutrients to the coastal waters. This study was to estimate the extent to which the rehabilitated mangrove of Rhizophora mucronata and Sonneratia alba contribute organic matter. This study was conducted from November 2015 to January 2016. Litter traps were used to collect the litter production and litterbags to measure decomposition rates. The results showed that the average of litter production for Sonneratia alba and Rhizophora mucronata was 4,38 g.m-2.day-1 and 3,61 g.m-2.day-1, respectively. However, Sonneratia alba apparently showed higher decay rates compare with Rhizophora mucronata. Nutrients element (N and P) released were 321,2 kg.ha-1.years-1 and 47,45 kg.ha-1.years-1 for Sonneratia alba; and 131,4 kg.ha-1.years-1 and 13,14 kg.ha-1.years-1 for Rhizophora mucronata. Overall, this study indicated that the mangrove rehabilitation in the area study contributed insignificantly carbon restocking the affected area, although it was able to provide ecological functions of this mangrove ecosystem.

POLAR DECOMPOSITION OF THE k-FOLD PRODUCT OF LEBESGUE MEASURE ON ℝn

The Blaschke–Petkantschin formula is a geometric measure decomposition of the q-fold product of Lebesgue measure on ℝn. Here we discuss another decomposition called polar decomposition by considering ℝn×⋯×ℝn as ℳn×k and using its polar decomposition. This is a generalisation of the Blaschke–Petkantschin formula and may be useful when one needs to integrate a function g:ℝn×⋯×ℝn→ℝ with rotational symmetry, that is, for each orthogonal transformation O,g(O(x1),…,O(xk))=g(x1,…xk). As an application we compute the moments of a Gaussian determinant.

Estimating the reduced moments of a random measure

We consider a random measure for which distribution is invariant under the action of a standard transformation group. The reduced moments are defined by applying classical theorems on invariant measure decomposition. We present a general method for constructing unbiased estimators of reduced moments. Several asymptotic results are established under an extension of the Brillinger mixing condition. Examples related to stochastic geometry are given.

Estimating the reduced moments of a random measure

We consider a random measure for which distribution is invariant under the action of a standard transformation group. The reduced moments are defined by applying classical theorems on invariant measure decomposition. We present a general method for constructing unbiased estimators of reduced moments. Several asymptotic results are established under an extension of the Brillinger mixing condition. Examples related to stochastic geometry are given.

Estimating the reduced moments of a random measure

Random measures are commonly used to describe geometrical properties of random sets. Examples are given by the counting measure associated with a point process, and the curvature measures associated with a random set with a smooth boundary. We consider a random measure with an invariant distribution under the action of a standard transformation group (translatioris, rigid motions, translations along a given direction and so on). In the framework of the theory of invariant measure decomposition, the reduced moments of the random measure are obtained by decomposing the related moment measures.

Estimating the reduced moments of a random measure

Random measures are commonly used to describe geometrical properties of random sets. Examples are given by the counting measure associated with a point process, and the curvature measures associated with a random set with a smooth boundary. We consider a random measure with an invariant distribution under the action of a standard transformation group (translatioris, rigid motions, translations along a given direction and so on). In the framework of the theory of invariant measure decomposition, the reduced moments of the random measure are obtained by decomposing the related moment measures.