Fecal pellet dynamics - #71

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Fecal pellet dynamics#71
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Fecal Pellets Egestion

Plastic particles are susceptible to be ingested and excreted by small organisms belonging to the zooplankton category.
After the egestion, they are incorporated into fecal pellets that differ in density from both virgin plastic and pure organic material. The presence of organic matter surrounding the plastic particle leads to a change in its overall density, thereby affecting its buoyancy. A particle that was initially buoyant may become negatively buoyant and sink or settle, depending on the density of the surrounding seawater. The reduction in the volume of organic matter leads to changes in the particle's density and, consequently, in its settling velocity, until the organic matter is completely degraded and the plastic particle returns to its initial state. The modeling of the dynamics of egested fecal pellets (+ plastic particles) has been developed following approach of @Omand2020.

In this framework, the settling velocity of a particle is computed based on the difference between the particle's density and that of the surrounding seawater. We assume that the organic matter enveloping the plastic particle is remineralized, as time passes by, according to the equation describing the variation of its equivalent radius: {math}a:

$$ \frac{\text{d}a}{\text{d}t} := - \text{C} \ \text{r} \ a^{\text{n}-2}. $$

Where $\text{C}$, $\text{r}$ and $\text{n}$ are the remineralization constant, the remineralization rate and a constant related to the type of remineralization.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
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Fecal pellet dynamics - #71

Open
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics
Open

Fecal pellet dynamics#71
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics

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Fecal Pellets Egestion

Plastic particles are susceptible to be ingested and excreted by small organisms belonging to the zooplankton category.
After the egestion, they are incorporated into fecal pellets that differ in density from both virgin plastic and pure organic material. The presence of organic matter surrounding the plastic particle leads to a change in its overall density, thereby affecting its buoyancy. A particle that was initially buoyant may become negatively buoyant and sink or settle, depending on the density of the surrounding seawater. The reduction in the volume of organic matter leads to changes in the particle's density and, consequently, in its settling velocity, until the organic matter is completely degraded and the plastic particle returns to its initial state. The modeling of the dynamics of egested fecal pellets (+ plastic particles) has been developed following approach of @Omand2020.

In this framework, the settling velocity of a particle is computed based on the difference between the particle's density and that of the surrounding seawater. We assume that the organic matter enveloping the plastic particle is remineralized, as time passes by, according to the equation describing the variation of its equivalent radius: {math}a:

$$ \frac{\text{d}a}{\text{d}t} := - \text{C} \ \text{r} \ a^{\text{n}-2}. $$

Where $\text{C}$, $\text{r}$ and $\text{n}$ are the remineralization constant, the remineralization rate and a constant related to the type of remineralization.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix"); } } catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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Fecal pellet dynamics - #71

Open
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics
Open

Fecal pellet dynamics#71
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics

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Fecal Pellets Egestion

Plastic particles are susceptible to be ingested and excreted by small organisms belonging to the zooplankton category.
After the egestion, they are incorporated into fecal pellets that differ in density from both virgin plastic and pure organic material. The presence of organic matter surrounding the plastic particle leads to a change in its overall density, thereby affecting its buoyancy. A particle that was initially buoyant may become negatively buoyant and sink or settle, depending on the density of the surrounding seawater. The reduction in the volume of organic matter leads to changes in the particle's density and, consequently, in its settling velocity, until the organic matter is completely degraded and the plastic particle returns to its initial state. The modeling of the dynamics of egested fecal pellets (+ plastic particles) has been developed following approach of @Omand2020.

In this framework, the settling velocity of a particle is computed based on the difference between the particle's density and that of the surrounding seawater. We assume that the organic matter enveloping the plastic particle is remineralized, as time passes by, according to the equation describing the variation of its equivalent radius: {math}a:

$$ \frac{\text{d}a}{\text{d}t} := - \text{C} \ \text{r} \ a^{\text{n}-2}. $$

Where $\text{C}$, $\text{r}$ and $\text{n}$ are the remineralization constant, the remineralization rate and a constant related to the type of remineralization.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms"); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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Fecal pellet dynamics - #71

Open
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics
Open

Fecal pellet dynamics#71
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics

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Fecal Pellets Egestion

Plastic particles are susceptible to be ingested and excreted by small organisms belonging to the zooplankton category.
After the egestion, they are incorporated into fecal pellets that differ in density from both virgin plastic and pure organic material. The presence of organic matter surrounding the plastic particle leads to a change in its overall density, thereby affecting its buoyancy. A particle that was initially buoyant may become negatively buoyant and sink or settle, depending on the density of the surrounding seawater. The reduction in the volume of organic matter leads to changes in the particle's density and, consequently, in its settling velocity, until the organic matter is completely degraded and the plastic particle returns to its initial state. The modeling of the dynamics of egested fecal pellets (+ plastic particles) has been developed following approach of @Omand2020.

In this framework, the settling velocity of a particle is computed based on the difference between the particle's density and that of the surrounding seawater. We assume that the organic matter enveloping the plastic particle is remineralized, as time passes by, according to the equation describing the variation of its equivalent radius: {math}a:

$$ \frac{\text{d}a}{\text{d}t} := - \text{C} \ \text{r} \ a^{\text{n}-2}. $$

Where $\text{C}$, $\text{r}$ and $\text{n}$ are the remineralization constant, the remineralization rate and a constant related to the type of remineralization.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links"); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + '
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Fecal pellet dynamics - #71

Open
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics
Open

Fecal pellet dynamics#71
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics

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@GaiaBuccino

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Fecal Pellets Egestion

Plastic particles are susceptible to be ingested and excreted by small organisms belonging to the zooplankton category.
After the egestion, they are incorporated into fecal pellets that differ in density from both virgin plastic and pure organic material. The presence of organic matter surrounding the plastic particle leads to a change in its overall density, thereby affecting its buoyancy. A particle that was initially buoyant may become negatively buoyant and sink or settle, depending on the density of the surrounding seawater. The reduction in the volume of organic matter leads to changes in the particle's density and, consequently, in its settling velocity, until the organic matter is completely degraded and the plastic particle returns to its initial state. The modeling of the dynamics of egested fecal pellets (+ plastic particles) has been developed following approach of @Omand2020.

In this framework, the settling velocity of a particle is computed based on the difference between the particle's density and that of the surrounding seawater. We assume that the organic matter enveloping the plastic particle is remineralized, as time passes by, according to the equation describing the variation of its equivalent radius: {math}a:

$$ \frac{\text{d}a}{\text{d}t} := - \text{C} \ \text{r} \ a^{\text{n}-2}. $$

Where $\text{C}$, $\text{r}$ and $\text{n}$ are the remineralization constant, the remineralization rate and a constant related to the type of remineralization.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default"); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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Fecal pellet dynamics - #71

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GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics
Open

Fecal pellet dynamics#71
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics

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Fecal Pellets Egestion

Plastic particles are susceptible to be ingested and excreted by small organisms belonging to the zooplankton category.
After the egestion, they are incorporated into fecal pellets that differ in density from both virgin plastic and pure organic material. The presence of organic matter surrounding the plastic particle leads to a change in its overall density, thereby affecting its buoyancy. A particle that was initially buoyant may become negatively buoyant and sink or settle, depending on the density of the surrounding seawater. The reduction in the volume of organic matter leads to changes in the particle's density and, consequently, in its settling velocity, until the organic matter is completely degraded and the plastic particle returns to its initial state. The modeling of the dynamics of egested fecal pellets (+ plastic particles) has been developed following approach of @Omand2020.

In this framework, the settling velocity of a particle is computed based on the difference between the particle's density and that of the surrounding seawater. We assume that the organic matter enveloping the plastic particle is remineralized, as time passes by, according to the equation describing the variation of its equivalent radius: {math}a:

$$ \frac{\text{d}a}{\text{d}t} := - \text{C} \ \text{r} \ a^{\text{n}-2}. $$

Where $\text{C}$, $\text{r}$ and $\text{n}$ are the remineralization constant, the remineralization rate and a constant related to the type of remineralization.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers"); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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Fecal pellet dynamics - #71

Open
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics
Open

Fecal pellet dynamics#71
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics

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Fecal Pellets Egestion

Plastic particles are susceptible to be ingested and excreted by small organisms belonging to the zooplankton category.
After the egestion, they are incorporated into fecal pellets that differ in density from both virgin plastic and pure organic material. The presence of organic matter surrounding the plastic particle leads to a change in its overall density, thereby affecting its buoyancy. A particle that was initially buoyant may become negatively buoyant and sink or settle, depending on the density of the surrounding seawater. The reduction in the volume of organic matter leads to changes in the particle's density and, consequently, in its settling velocity, until the organic matter is completely degraded and the plastic particle returns to its initial state. The modeling of the dynamics of egested fecal pellets (+ plastic particles) has been developed following approach of @Omand2020.

In this framework, the settling velocity of a particle is computed based on the difference between the particle's density and that of the surrounding seawater. We assume that the organic matter enveloping the plastic particle is remineralized, as time passes by, according to the equation describing the variation of its equivalent radius: {math}a:

$$ \frac{\text{d}a}{\text{d}t} := - \text{C} \ \text{r} \ a^{\text{n}-2}. $$

Where $\text{C}$, $\text{r}$ and $\text{n}$ are the remineralization constant, the remineralization rate and a constant related to the type of remineralization.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode"); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })();
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Fecal pellet dynamics - #71

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GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics
Open

Fecal pellet dynamics#71
GaiaBuccino wants to merge 3 commits into
Parcels-code:mainfrom
GaiaBuccino:fecal_pellet-dynamics

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Fecal Pellets Egestion

Plastic particles are susceptible to be ingested and excreted by small organisms belonging to the zooplankton category.
After the egestion, they are incorporated into fecal pellets that differ in density from both virgin plastic and pure organic material. The presence of organic matter surrounding the plastic particle leads to a change in its overall density, thereby affecting its buoyancy. A particle that was initially buoyant may become negatively buoyant and sink or settle, depending on the density of the surrounding seawater. The reduction in the volume of organic matter leads to changes in the particle's density and, consequently, in its settling velocity, until the organic matter is completely degraded and the plastic particle returns to its initial state. The modeling of the dynamics of egested fecal pellets (+ plastic particles) has been developed following approach of @Omand2020.

In this framework, the settling velocity of a particle is computed based on the difference between the particle's density and that of the surrounding seawater. We assume that the organic matter enveloping the plastic particle is remineralized, as time passes by, according to the equation describing the variation of its equivalent radius: {math}a:

$$ \frac{\text{d}a}{\text{d}t} := - \text{C} \ \text{r} \ a^{\text{n}-2}. $$

Where $\text{C}$, $\text{r}$ and $\text{n}$ are the remineralization constant, the remineralization rate and a constant related to the type of remineralization.

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