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Carbon sequestration in a changing climate

                 Table 1. List of variables
                 Variable type  Variable name     Symbol used  Measurement/formula       Unit           Data source
                 Dependent     Carbon             FCBI         (Forest rents as % of GDP-   Index       World Bank 69
                 variable      sequestration                   net forest depletion as % of   (dimensionless)
                               capacity                        GNI)/CO emissions (metric
                                                                       2
                                                               tons per capita)
                 Independent   Agricultural income  AGRINC     Agriculture, forestry, and   USD (current)  World Bank 69
                 variables                                     fishing value added (current
                                                               USD)
                               Annual             DEFORATE     ([Forest area year 2 -forest   Percentage (%)  World Bank 69
                               deforestation rate              area year 1]/forest area year
                                                               1)×100
                               Forest management   FMCP        (Forest rents as % of     Index          World Bank 69
                               and conservation                GDP+Agricultural value    (dimensionless)
                               policies                        added as % of GDP)/R&D
                                                               expenditures as % of GDP
                               Climatic variables   TEMP       Annual mean temperature   Degrees Celsius   CCKP 70
                               — temperature                   change                    (°C)
                               change
                               Climatic variables   RAINFALL   Annual total precipitation  Millimeters   CCKP 70
                               — rainfall                                                (mm/year)
                               Population and     URBANPOP     Urban population as       Percentage (%)  World Bank 69
                               land use change —               a percentage of total
                               urban population                population
                 Abbreviations: CCKP: Climate Change Knowledge Portal; CO2: Carbon dioxide; FCBI: Forest Carbon Benefit Indicator; GDP: Gross
                 domestic product; GNI: Gross national income; R&D: Research and development; USD: United States dollars.

                behavior, social development, and economic activities.    which minimizes the sum of squared residuals, robust
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                This concept is critical  for understanding how plants   regression  utilizes  several  optimization  methods  to
                store carbon in response to climate change. Temperature   reduce the influence of outliers on model predictions.
                and precipitation regulate plant growth, soil fertility, and   As a result, RLS provides more reliable and unbiased
                carbon sequestration, among other ecological processes.   parameter  estimates  for datasets  with  non-normal
                Moderate temperatures and abundant rainfall enhance   error distributions or extreme values.  This technique
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                forest  carbon  storage,  while  extreme  heat  waves and   is particularly  valuable  when studying carbon
                droughts reduce  forest  productivity  and  contribute  to   sequestration, agricultural income, deforestation, forest
                deforestation.  Human efforts to maintain and conserve   management,  climatic  factors, and land use changes.
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                forests  are  influenced  by  climate  and  geography,    In an OLS model, outliers often include extreme
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                particularly  through  factors  such  as  urbanization,   meteorological  variables,  such as precipitation  and
                land use, and agriculture.  This hypothesis can guide   temperature,  or rapid changes in forest cover, such
                researchers  in  studying  how environmental  factors   as deforestation.  The RLS approach improves the
                affect  forest  carbon  sequestration  and  how  societies   model by reducing extreme values, providing a clearer
                have adapted to these constraints through sustainable   presentation of variable patterns and correlations. 79
                policies and practices.                                Environmental and socioeconomic variables typically
                  The study employed an analytical  model to        exhibit varied error rates; therefore, robust regression
                provide statistically robust insights into forest carbon   accounts for this error.  Through the use of iteratively
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                benefits and critical socioeconomic and environmental   reweighted least squares, robust regression updates data
                challenges.  RLS regression was used for empirical   weights,  reducing  the  influence  of  observations  with
                estimations.  RLS  regression  effectively  manages   higher  residuals  to  stabilize  model  fit.  Despite  such
                outliers and heteroskedasticity  in complex  datasets,   variations, robust regression ensures the validity of the
                making  it especially  useful when ordinary least   study. Minimizing the impact of outliers in population
                squares (OLS) assumptions are violated.  Unlike OLS,   growth,  land  use,  and  carbon  sequestration  policy
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                Volume 22 Issue 1 (2025)                        57                           doi: 10.36922/AJWEP025050027
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