Tree diversity and vegetation dynamics of a one hectare forest plot census in the lowland rain forests of the Piedras Blancas National Park ("Regenwald der Österreicher"), Costa Rica

Der Esquinas Regenwald in Costa Rica gehört zu den artenreichsten Pflanzengesellschaften in Mittelamerika (QUESADA et al 1997). Diese Diplomarbeit beschreibt die Struktur und floristische Diversität eines Forschungsplots in einem Primärwald im Piedras Blancas Nationalpark (“Esquinas rainforest” oder "Regenwald der Österreicher"), welcher in einer Seehöhe von 300-336 msm und einer geographischen Lage von N 8°41’ und W 83°12’ auf einem gut drainagierten südwestlich exponierten Hangwald liegt. Der durchschnittliche jährliche Niederschlag liegt bei etwa 6000 mm, die jährliche Durchschnittstemperatur bei ca. 28°C. Diese Eigenschaften sowie die Abwesenheit einer ausgeprägten Trockenzeit führten zur Ausbildung eines „Perhumid tropical lowland wet forest“ gemäß HOLDRIDGE et al 1971. Die Feldaufnahmen wurden zwischen 2000 und 2001 durchgeführt. Diese wurden in Form von Besammlungen und Bestimmungen von holzigen Pflanzen mit einem Brusthöhendurchmesser (dbh) ≥ 10 cm sowie ≥ 2 cm dbh durchgeführt. Ein detaillierter Lageplan wurde erstellt, Daten jedes einzelnen Individuums und der gesamten Untersuchungsfläche erhoben mit laufender Nummer, dbh, Baumhöhe, Bestandesgrundfläche und Biomasse. Weiters wurden Wachstums- und Mortalitätsraten sowie verschiedene Artendichte- und Diversitätsindices (Simpson, Shannon-Wiener, Fisher´s α), Importance Value (IVI) und Family Importance Value (FIVI) berechnet. Alle Berechnungen wurden mit jenen aus früheren Studien von HUBER (1996a, 2005) und WEISSENHOFER (1996, 2005) verglichen. Insgesamt 2849 Individuen aus 232 Arten ≥ 2 cm dbh sowie 453 Individuen aus 108 Arten ≥ 10 cm dbh wurden ermittelt. Palmen wiesen eine ausgesprochene Häufigkeit vor allem mit den Arten Iriartea deltoidea (62 Individuen) und Welfia regia (43 Individuen) für alle Individuen dbh ≥ 10 cm auf. Bei den niederen Größenklassen traten Unterbauarten wie Henriettea tuberculata (Melastomataceae) und Psychotria elata (Rubiaceae) sehr häufig auf (184 bzw. 145 Individuen). Die graphische Darstellung der Größenklassenverteilung zeigt die typische reverse J-Kurve mit den meisten Individuen in den niederen Größenklassen. Der durchschnittliche dbh aller Individuen ≥ 10 cm betrug 25.9 cm, im Jahr 1993 23.5 cm. Der durchschnittliche dbh aller Individuen ≥ 2 cm betrug 7.0 cm. Die Bestandesgrundfläche betrug 35.9 m² (dbh ≥ 10 cm) beziehungsweise 38.7 m² (dbh ≥ 2 cm). Dieses Ergebnis liegt im unteren Bereich verglichen mit ähnlich designten Studien in lateinamerikanischen Wäldern. Es wurde ein ähnliches Ergebnis wie bei WEISSENHOFER (2005) erzielt, welcher 35.5 m² in 1993 ermittelte. Hauptgrund einer niedrigeren Bestandesgrundfläche sind schwere Störungen in den vergangenen Jahren mit Ausfällen von Individuen mit höherem dbh. Das Relief ist ebenfalls ein für die Bestandesgrundfläche entscheidender Parameter. WEISSENHOFER (2005) zeigte höchste Bestandesgrundfläche auf steileren Untersuchungsflächen sowie auf Rücken (bis zu 43.5 m²). HARTSHORN (1983) ermittelte ebenfalls höhere Bestandesgrundflächen auf Steilhängen und Rücken (bis zu 45.8 m²), sowie niedrigere in flacheren Beständen desselben Areals. Der Esquinas Forschungsplot weist mit 339 Mg ha-1 eine durchschnittliche Biomasse im Vergleich mit anderen tropischen Wäldern auf. WEISSENHOFER ermittelte 315 Mg ha-1 in 1993. Die Biomasseakkumulation (Nettoprimärproduktion) war mit 7.9 Mg ha-1 y-1 hoch. Die Zuwachsrate (Netto-Ökosystemproduktion oder Biomassezunahme abzüglich Verluste durch Absterben) lag mit 1.9 Mg ha-1 y-1 im typischen Bereich vergleichbarer tropischer Wälder. Die hohe Nettoprimärproduktion kann durch den hohen Anteil an gap-Fläche im unteren Bereich des Plots erklärt werden. Hohe Produktionswerte charakterisieren typische Sekundärwälder und Primärwälder mit einem höheren Anteil an gap-Areal. Die Mortlitätsrate betrug 3.54 % y-1 für alle Individuen dbh ≥ 10 cm. Mortalität war ungleich über die Größenklassen verteilt. Höhere Raten traten in den niedrigeren Klassen auf. Beinahe 60 % aller ausgefallenen Individuen wiesen einen dbh unter 15 cm auf. Über die höheren Klassen verlief die Mortalität nahezu konstant. Die Einwuchsraten betrugen 1.29 % y-1 für alle Individuen dbh ≥ 10 cm. Auf der Untersuchungsfläche wurden 232 Arten aus 59 Familien bestimmt. Die Palmen Iriartea deltoidea und Welfia regia wie auch die Clusiaceae Symphonia globulifera und Marila laxiflora sowie Carapa guianensis (Meliaceae) waren sehr häufig. Viele Unterwuchspflanzen sowie Besiedler von Störungsregimes, Arten der Familien Rubiaceae und Melastomataceae (eg. Psychotria elata, Isertia laevis, Henriettea tuberculata) traten ebenfalls ausgesprochen oft auf. Eine hohe Abundanz an Palmen ist charakteristisch für sehr humide Wälder sowie Bestände in denen Störungen häufig auftreten. 57 Arten traten nur mit einem Individuum auf. Der Shannon-Wiener Index betrug H´= 6.427, Simpson Index ergab D = 0.035, der Simpson Diversitätsindex 1-D = 0.965 und Alpha Index betrug α = 59.699. Die Familien mit dem höchsten FIVI waren die Arecaceae (33.846), Moraceae (26.648), Rubiaceae (22.134) und die Clusiaceae (19.075). Die Arten mit dem höchsten IVI waren Welfia regia (Arecaceae; 17.277), Brosimum utile (Moraceae; 16.432), Carapa guianensis (Meliaceae; 15.838) und Iriartea deltoidea (Arecaceae; 10.192). Diese ausgesprochen hohe Diversität des Esquinas Regenwalds ist darauf zurückzuführen, dass hohe Niederschläge, keine ausgeprägte Trockenzeit, stark strukturierte Bestände sowie heterogene Böden dieses System charakterisieren.The Esquinas rainforest in Costa Rica is among the plant communities with the highest number of species in Central America (QUESADA et al 1997). The thesis describes the structure and the floristic diversity of a research plot of an undisturbed primary forest in the Piedras Blancas / Esquinas National Park ("Regenwald der Österreicher"). The data were collected between 2000 and 2001. Analyses were performed collecting and identifying woody plants of ≥ 10 cm and ≥ 2 cm dbh respectively. A detailed site map was generated, data were collected and calculated of each tree and the whole plot with individual number, diameter in breast height (dbh), tree height, basal area (BA), and biomass. Further growth and mortality rates were calculated. Furthermore species density, diversity indices (Simpson, Shannon-Wiener, Fisher´s α), Importance Value (IVI) and Family Importance Value (FIVI) were calculated. All data were compared with former studies performed by HUBER (1996a, 2005) and WEISSENHOFER (1996, 2005) In total 2849 individuals of 232 species ≥ 2 cm dbh and 453 individuals of 108 species ≥ 10 cm dbh were recorded. Palms were very abundant with the most frequent species Iriartea deltoidea (62 individuals) and Welfia regia (43 individuals) for all trees dbh ≥ 10 cm. In the lower size classes understorey species like Henriettea tuberculata (Melastomataceae) and Psychotria elata (Rubiaceae) were very frequent with 184 and 145 individuals respectively. The graph of the size class distribution showed the anticipated J graph. The average dbh of all individuals ≥ 10 cm was 25.9 cm, in 1993 23.5 cm. The average dbh of all individuals ≥ 2 cm was 7.0 cm. The BA was 35.9 m² (dbh ≥ 10 cm) and 38.7 m² (dbh ≥ 2 cm), an amount found on the lower range in similar studies in Latin American forests. Compared to WEISSENHOFER (2005) who calculated 35.5 m² in 1993 similar values could be reported. Root causes of lower BA were suffering several severe disturbances in the past years with loss of many bigger trees. Also relief was deciding the amount of BA. WEISSENHOFER (2005) showed highest BA on plots with higher slopes and on ridges (up to 43.5 m²). HARTSHORN (1983) confirmed this statement with BA of 45.8 m² on those stands and lower values on sites with lower gradients in the same area. The Esquinas research plot showed average biomass (339 Mg ha-1) compared to other tropical forests. WEISSENHOFER calculated 315 Mg ha-1 in 1993. Biomass accumulation (net primary production NPP) was high with 7.9 Mg ha-1 y-1. Ingrowth rate (net ecosystem production NEP or uptake of biomass minus losses through death) was with 1.9 Mg ha-1 y-1 in the range of comparable tropical forests. The high NPP could be explained with the great gap-similar area in the lower part of the research plot. High NPP values are typical for secondary forests and primary forests with high amount of gap areal. The mortality rate was 3.54 % y-1for all stems dbh ≥ 10 cm. The size class distribution for mortality was different. Lower size classes showed a higher rate. Nearly 60 % of all dead individuals were below dbh 15 cm. In the higher size classes mortality was nearly constant. Recruitment was 1.29 % y-1 for all stems dbh ≥ 10 cm. In the research plot 232 species out of 59 families occurred. The palms Iriartea deltoidea and Welfia regia as well as the Clusiaceae Symphonia globulifera and Marila laxiflora as well as Carapa guianensis (Meliaceae) were very common. Many understorey and disturbance species of the families Rubiaceae and Melastomataceae (eg. Psychotria elata, Isertia laevis, Henriettea tuberculata) were also characterized by a very high abundance. Due to the high disturbance degree of the research plot palms were very frequent in different succession phases, a characteristic where disturbances frequently occur and results in gaps or gap areas in the forests. 57 ssp. were represented with only one individual. The Shannon-Wiener index was H´= 6.427, Simpson index gave D = 0.035, Simpson index of diversity 1-D = 0.965 and Alpha index α = 59.699. The families with the highest FIVI were the Arecaceae (33.846), Moraceae (26.648) Rubiaceae (22.134) and the Clusiaceae (19.075). The species with the highest IVI were Welfia regia (Arecaceae; 17.277), Brosimum utile (Moraceae; 16.432), Carapa guianensis (Meliaceae; 15.838) and Iriartea deltoidea (Arecaceae; 10.192). Probably due to the high precipitation, the missing dry season, the strong structured landscape and soil heterogeneity the Esquinas forest has a very high species diversity for a tropical forest

Survival in primary hemophagocytic lymphohistiocytosis, 2016 to 2021: etoposide is better than its reputation

Böhm S, Wustrau K, Pachlopnik Schmid J, et al. Survival in primary hemophagocytic lymphohistiocytosis, 2016 to 2021: etoposide is better than its reputation. Blood. 2024;143(10):872-881.ABSTRACT: Primary hemophagocytic lymphohistiocytosis (pHLH) is a life-threatening hyperinflammatory syndrome that develops mainly in patients with genetic disorders of lymphocyte cytotoxicity and X-linked lymphoproliferative syndromes. Previous studies with etoposide-based treatment followed by hematopoetic stem cell transplantation (HSCT) resulted in 5-year survival of 50% to 59%. Contemporary data are lacking. We evaluated 88 patients with pHLH documented in the international HLH registry from 2016-2021. In 12 of 88 patients, diagnosis was made without HLH activity, based on siblings or albinism. Major HLH-directed drugs (etoposide, antithymocyte globulin, alemtuzumab, emapalumab, ruxolitinib) were administered to 66 of 76 patients who were symptomatic (86% first-line etoposide); 16 of 57 patients treated with etoposide and 3 of 9 with other first-line treatment received salvage therapy. HSCT was performed in 75 patients; 7 patients died before HSCT. Three-year probability of survival (pSU) was 82% (confidence interval [CI], 72%-88%) for the entire cohort and 77% (CI, 64%-86%) for patients receiving first-line etoposide. Compared with the HLH-2004 study, both pre-HSCT and post-HSCT survival of patients receiving first-line etoposide improved, 83% to 91% and 70% to 88%. Differences to HLH-2004 included preferential use of reduced-toxicity conditioning and reduced time from diagnosis to HSCT (from 148 to 88 days). Three-year pSU was lower with haploidentical (4 of 9 patients [44%]) than with other donors (62 of 66 [94%]; P< .001). Importantly, early HSCT for patients who were asymptomatic resulted in 100% survival, emphasizing the potential benefit of newborn screening. This contemporary standard-of-care study of patients with pHLH reveals that first-line etoposide-based therapy is better than previously reported, providing a benchmark for novel treatment regimes. © 2024 American Society of Hematology. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies

Survival in primary hemophagocytic lymphohistiocytosis, 2016 to 2021: etoposide is better than its reputation

Primary hemophagocytic lymphohistiocytosis (pHLH) is a life-threatening hyperinflammatory syndrome that develops mainly in patients with genetic disorders of lymphocyte cytotoxicity and X-linked lymphoproliferative syndromes. Previous studies with etoposide-based treatment followed by hematopoetic stem cell transplantation (HSCT) resulted in 5-year survival of 50% to 59%. Contemporary data are lacking. We evaluated 88 patients with pHLH documented in the international HLH registry from 2016-2021. In 12 of 88 patients, diagnosis was made without HLH activity, based on siblings or albinism. Major HLH-directed drugs (etoposide, antithymocyte globulin, alemtuzumab, emapalumab, ruxolitinib) were administered to 66 of 76 patients who were symptomatic (86% first-line etoposide); 16 of 57 patients treated with etoposide and 3 of 9 with other first-line treatment received salvage therapy. HSCT was performed in 75 patients; 7 patients died before HSCT. Three-year probability of survival (pSU) was 82% (confidence interval [CI], 72%-88%) for the entire cohort and 77% (CI, 64%-86%) for patients receiving first-line etoposide. Compared with the HLH-2004 study, both pre-HSCT and post-HSCT survival of patients receiving first-line etoposide improved, 83% to 91% and 70% to 88%. Differences to HLH-2004 included preferential use of reduced-toxicity conditioning and reduced time from diagnosis to HSCT (from 148 to 88 days). Three-year pSU was lower with haploidentical (4 of 9 patients [44%]) than with other donors (62 of 66 [94%]; P < .001). Importantly, early HSCT for patients who were asymptomatic resulted in 100% survival, emphasizing the potential benefit of newborn screening. This contemporary standard-of-care study of patients with pHLH reveals that first-line etoposide-based therapy is better than previously reported, providing a benchmark for novel treatment regimes

Survival in primary hemophagocytic lymphohistiocytosis 2016-2021: etoposide is better than its reputation

Primary hemophagocytic lymphohistiocytosis (pHLH) is a life-threatening hyperinflammatory syndrome that develops mainly in patients with genetic disorders of lymphocyte cytotoxicity and X-linked lymphoproliferative syndromes. Previous studies with etoposide-based treatment followed by hematopoetic stem cell transplantation (HSCT) resulted in 50-59% 5-year survival. Contemporary data are lacking. We evaluated 88 pHLH patients documented in the international HLH Registry between 2016-2021 with follow-up until 6/2023. In 12/88 patients, the diagnosis was made without HLH activity, based on index siblings or partial albinism. Major HLH-directed drugs (etoposide, ATG, alemtuzumab, emapalumab, ruxolitinib) were given to 66/76 symptomatic patients (86% first-line etoposide); 16/57 etoposide-treated and 3/9 patients with other first-line treatment received salvage therapy. HSCT was performed in 75 patients, 7 symptomatic patients died before HSCT. 3-year probability of survival (pSU) was 82% (CI 72%-88%) for the entire cohort and 77% (CI 64-86%) for symptomatic patients receiving first-line etoposide. Compared to the HLH-2004 study, both pre-HSCT survival (83% to 91%) and post-HSCT survival of patients receiving first-line etoposide improved (70% to 88%). Differences to HLH-2004 included preferential use of reduced-toxicity conditioning and reduced time from diagnosis to HSCT (148 to 88 days). 3-year pSU was lower with haploidentical (44%, 4/9 patients) than with other types of donors (94%, 4/66, p&lt;0.001). Importantly, also in this study, early HSCT of asymptomatic patients resulted in excellent survival (100%), emphasizing the potential benefit of newborn screening. This contemporary standard-of-care study of pHLH patients reveals that first-line etoposide-based therapy is better than previously reported, providing a benchmark for novel treatment regimes