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  <xsd:element name="FinancialInstrumentsOffBalanceSheetRisksAndContingenciesAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_FinancialInstrumentsOffBalanceSheetRisksAndContingenciesAbstract" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_DisclosureOfFairValueOffBalanceSheetRisksTextBlock" name="DisclosureOfFairValueOffBalanceSheetRisksTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="FinancialHighlightsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_FinancialHighlightsAbstract" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_SupplementalFinancialInformationDisclosureTextBlock" name="SupplementalFinancialInformationDisclosureTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="NetAssetValuePolicyTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_NetAssetValuePolicyTextBlock" substitutionGroup="xbrli:item" />
  <xsd:element name="EarningsPerUnitPolicyTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_EarningsPerUnitPolicyTextBlock" substitutionGroup="xbrli:item" />
  <xsd:element name="OtherOperatingIncomeExpensePolicyTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_OtherOperatingIncomeExpensePolicyTextBlock" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_BrokerageCommissionsTableTextBlock" name="BrokerageCommissionsTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="unl_PerUnitPerformanceDataAndOtherSupplementalFinancialDataTableTextBlock" name="PerUnitPerformanceDataAndOtherSupplementalFinancialDataTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable" substitutionGroup="xbrldt:hypercubeItem" />
  <xsd:element name="CreationBasketsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_CreationBasketsMember" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems" name="OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfUnitsPerBasket" type="srt-types:perUnitItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="unl_NumberOfUnitsPerBasket" substitutionGroup="xbrli:item" />
  <xsd:element name="FeePaidPerOrder" type="srt-types:perUnitItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="unl_FeePaidPerOrder" substitutionGroup="xbrli:item" />
  <xsd:element name="UnitsIssuedDuringPeriodUnitsNewIssues" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_UnitsIssuedDuringPeriodUnitsNewIssues" substitutionGroup="xbrli:item" />
  <xsd:element name="UnitsIssuedDuringPeriodValueNewIssues" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_UnitsIssuedDuringPeriodValueNewIssues" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <xsd:element name="SignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_SignificantAccountingPoliciesTable" substitutionGroup="xbrldt:hypercubeItem" />
  <xsd:element name="RedemptionBasketsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_RedemptionBasketsMember" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="RelatedPublicFundsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_RelatedPublicFundsMember" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_FeesPaidAndRelatedPartyTransactionsLineItems" name="FeesPaidAndRelatedPartyTransactionsLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="BaseFeePercentage" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_BaseFeePercentage" substitutionGroup="xbrli:item" />
  <xsd:element name="RebalancingInvestmentsTransactionMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_RebalancingInvestmentsTransactionMember" substitutionGroup="xbrli:item" />
  <xsd:element name="CreationAndRedemptionActivityMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_CreationAndRedemptionActivityMember" substitutionGroup="xbrli:item" />
  <xsd:element name="PercentageOfAverageDailyNetAssets" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="unl_PercentageOfAverageDailyNetAssets" substitutionGroup="xbrli:item" />
  <xsd:element name="MarketingAgreementMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_MarketingAgreementMember" substitutionGroup="xbrli:item" />
  <xsd:element name="GroupFourMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_GroupFourMember" substitutionGroup="xbrli:item" />
  <xsd:element name="GroupFiveMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_GroupFiveMember" substitutionGroup="xbrli:item" />
  <xsd:element name="BasisAmountForFeePercentage" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="unl_BasisAmountForFeePercentage" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <xsd:element name="CommissionsPaid" type="srt-types:perUnitItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_CommissionsPaid" substitutionGroup="xbrli:item" />
  <xsd:element name="MaximumAggregateCompensationPaidForDistributionRelatedServices" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_MaximumAggregateCompensationPaidForDistributionRelatedServices" substitutionGroup="xbrli:item" />
  <xsd:element name="TotalIncomeLossPerUnit" type="dtr-types:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_TotalIncomeLossPerUnit" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_TotalExpensesPerUnit" name="TotalExpensesPerUnit" nillable="true" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="IncreaseDecreaseInNetAssetValuePerUnit" type="dtr-types:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_IncreaseDecreaseInNetAssetValuePerUnit" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_RateOfReturnOnAverageAsset" name="RateOfReturnOnAverageAsset" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="AverageNetAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_AverageNetAssetsAbstract" substitutionGroup="xbrli:item" />
  <xsd:element name="PercentageOfTotalRevenue" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_PercentageOfTotalRevenue" substitutionGroup="xbrli:item" />
  <xsd:element name="ManagementIncentiveFeePercentage" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_ManagementIncentiveFeePercentage" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_ExpensesExcludingManagementFeePercentage" name="ExpensesExcludingManagementFeePercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="PercentageWaiverExpense" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_PercentageWaiverExpense" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_ExpenseExcludingManagementFeePercentageNet" name="ExpenseExcludingManagementFeePercentageNet" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="PercentageOfConsolidatedNetIncome" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="unl_PercentageOfConsolidatedNetIncome" substitutionGroup="xbrli:item" />
  <xsd:element name="ClosedPositionsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_ClosedPositionsMember" substitutionGroup="xbrli:item" />
  <xsd:element name="OpenPositionMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="unl_OpenPositionMember" substitutionGroup="xbrli:item" />
  <xsd:element id="unl_PercentageOfContractualObligatedToPay" name="PercentageOfContractualObligatedToPay" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="unl_CashAndCashEquivalentsInTradingAccounts" name="CashAndCashEquivalentsInTradingAccounts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="unl_MarketingAgentAndAffiliateOfUscfMember" name="MarketingAgentAndAffiliateOfUscfMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_DerivativeNatureTypeAxis" name="DerivativeNatureTypeAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_DerivativeNatureTypeDomain" name="DerivativeNatureTypeDomain" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_DirectorsFeesPayableCurrentAndNoncurrent" name="DirectorsFeesPayableCurrentAndNoncurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="unl_PeriodAxis" name="PeriodAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_PeriodDomain" name="PeriodDomain" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_UnitedStates12MonthNaturalGasFundMember" name="UnitedStates12MonthNaturalGasFundMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_OpenFuturesContractsLongMember" name="OpenFuturesContractsLongMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_InvestmentSecuritiesSeriesOneAxis" name="InvestmentSecuritiesSeriesOneAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_InvestmentsecuritiesseriesoneDomain" name="InvestmentsecuritiesseriesoneDomain" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_NymexnaturalgasfuturesngthirteenMember" name="NymexnaturalgasfuturesngthirteenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_NymexNaturalGasFuturesngForteenMember" name="NymexNaturalGasFuturesngForteenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_NymexNaturalGasFuturesngFifteenMember" name="NymexNaturalGasFuturesngFifteenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_IncreaseDecreaseInPrepaidLicenseFees" name="IncreaseDecreaseInPrepaidLicenseFees" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" abstract="false" />
  <xsd:element id="unl_NymexNaturalGasFuturesngSixteenMember" name="NymexNaturalGasFuturesngSixteenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_NymexNaturalGasFuturesngSeventeenMember" name="NymexNaturalGasFuturesngSeventeenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_NymexNaturalGasFuturesngEighteenMember" name="NymexNaturalGasFuturesngEighteenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_GoldmanSachsFinancialSquareGovernmentFundInstitutionalSharesMember" name="GoldmanSachsFinancialSquareGovernmentFundInstitutionalSharesMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_RbcU.s.GovernmentMoneyMarketFundInstitutionalShares0.03Member" name="RbcU.s.GovernmentMoneyMarketFundInstitutionalShares0.03Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_NymexNaturalGasFuturesNgTwentyEightMember" name="NymexNaturalGasFuturesNgTwentyEightMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_NymexNaturalGasFuturesNgTwentyNineMember" name="NymexNaturalGasFuturesNgTwentyNineMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="unl_NymexNaturalGasFuturesNgThirtyMember" name="NymexNaturalGasFuturesNgThirtyMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfSharesRegisteredInPeriod" id="unl_NumberOfSharesRegisteredInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NumberOfRegisteredShares" id="unl_NumberOfRegisteredShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EstimatedCosts" id="unl_EstimatedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NumberOfSuccessiveValuationDays" id="unl_NumberOfSuccessiveValuationDays" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AverageDailyPercentageChangeInPriceOfBenchmarkFuturesContractConsidered" id="unl_AverageDailyPercentageChangeInPriceOfBenchmarkFuturesContractConsidered" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ExcessExpensesPercentageForReimbursementToOthersPercentage" id="unl_ExcessExpensesPercentageForReimbursementToOthersPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PrepaidLicenseFees" id="unl_PrepaidLicenseFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="Nymexnaturalgasfuturesngfebruary2023contractsexpiringjanuary2023Member" id="unl_Nymexnaturalgasfuturesngfebruary2023contractsexpiringjanuary2023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NymexNaturalGasFuturesNgMarch2023ContractsExpiringFebruary2023Member" id="unl_NymexNaturalGasFuturesNgMarch2023ContractsExpiringFebruary2023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NymexNaturalGasFuturesNgApril2023ContractsExpiringMarch2023Member" id="unl_NymexNaturalGasFuturesNgApril2023ContractsExpiringMarch2023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
