diff --git a/frontend/src/api/steady/steadyDataView/interface/index.ts b/frontend/src/api/steady/steadyDataView/interface/index.ts
index a0bb8c0..e1f5a72 100644
--- a/frontend/src/api/steady/steadyDataView/interface/index.ts
+++ b/frontend/src/api/steady/steadyDataView/interface/index.ts
@@ -42,7 +42,6 @@ export namespace SteadyDataView {
         statTypes: SteadyTrendStatType[]
         timeStart: string
         timeEnd: string
-        bucket?: string
         qualityFlag?: number
         harmonicOrders?: number[]
     }
diff --git a/frontend/src/views/steady/steadyDataView/components/SteadyIndicatorFloatingPanel.vue b/frontend/src/views/steady/steadyDataView/components/SteadyIndicatorFloatingPanel.vue
index 08cd059..4a70e59 100644
--- a/frontend/src/views/steady/steadyDataView/components/SteadyIndicatorFloatingPanel.vue
+++ b/frontend/src/views/steady/steadyDataView/components/SteadyIndicatorFloatingPanel.vue
@@ -19,6 +19,7 @@
                 :key="selectorResetKey"
                 :tree-data="treeData"
                 :loading="loading"
+                :default-checked-keys="defaultCheckedKeys"
                 @refresh="emit('refresh')"
                 @change="emit('change', $event)"
             />
@@ -39,6 +40,7 @@ defineProps<{
     collapsed: boolean
     treeData: SteadyDataView.SteadyIndicatorNode[]
     loading: boolean
+    defaultCheckedKeys: string[]
     selectorResetKey: number
 }>()
 
diff --git a/frontend/src/views/steady/steadyDataView/components/SteadyIndicatorTree.vue b/frontend/src/views/steady/steadyDataView/components/SteadyIndicatorTree.vue
index bb22678..1f4d349 100644
--- a/frontend/src/views/steady/steadyDataView/components/SteadyIndicatorTree.vue
+++ b/frontend/src/views/steady/steadyDataView/components/SteadyIndicatorTree.vue
@@ -13,6 +13,7 @@
                 node-key="treeKey"
                 show-checkbox
                 default-expand-all
+                :default-checked-keys="defaultCheckedKeys"
                 :expand-on-click-node="false"
                 :props="{ label: 'name', children: 'children' }"
                 @check="handleCheck"
@@ -29,7 +30,7 @@
 </template>
 
 <script setup lang="ts">
-import { computed, ref } from 'vue'
+import { computed, nextTick, ref, watch } from 'vue'
 import { Refresh } from '@element-plus/icons-vue'
 import type { TreeInstance } from 'element-plus'
 import type { SteadyDataView } from '@/api/steady/steadyDataView/interface'
@@ -42,6 +43,7 @@ defineOptions({
 const props = defineProps<{
     treeData: SteadyDataView.SteadyIndicatorNode[]
     loading: boolean
+    defaultCheckedKeys: string[]
 }>()
 
 const emit = defineEmits<{
@@ -70,6 +72,19 @@ const handleCheck = () => {
     const checkedNodes = (treeRef.value?.getCheckedNodes(false, false) || []) as SteadyDataView.SteadyIndicatorNode[]
     emit('change', collectLeafIndicators(checkedNodes))
 }
+
+const applyDefaultCheckedKeys = async () => {
+    await nextTick()
+    treeRef.value?.setCheckedKeys(props.defaultCheckedKeys, false)
+}
+
+watch(
+    () => [normalizedTreeData.value, props.defaultCheckedKeys],
+    () => {
+        applyDefaultCheckedKeys()
+    },
+    { immediate: true }
+)
 </script>
 
 <style scoped lang="scss">
diff --git a/frontend/src/views/steady/steadyDataView/components/SteadyLedgerTree.vue b/frontend/src/views/steady/steadyDataView/components/SteadyLedgerTree.vue
index 8f2d003..b3b7635 100644
--- a/frontend/src/views/steady/steadyDataView/components/SteadyLedgerTree.vue
+++ b/frontend/src/views/steady/steadyDataView/components/SteadyLedgerTree.vue
@@ -20,13 +20,19 @@
                 node-key="id"
                 show-checkbox
                 default-expand-all
+                :default-checked-keys="defaultCheckedKeys"
                 :expand-on-click-node="false"
                 :props="{ label: 'name', children: 'children' }"
                 @check="handleCheck"
             >
                 <template #default="{ data }">
                     <div class="tree-node">
-                        <span class="node-name">{{ data.name }}</span>
+                        <span class="node-main">
+                            <el-icon :class="['node-icon', `is-level-${normalizeLedgerLevel(data.level)}`]">
+                                <component :is="resolveLedgerIcon(data.level)" />
+                            </el-icon>
+                            <span class="node-name">{{ data.name }}</span>
+                        </span>
                         <span class="node-count">
                             <template v-if="Number(data.deviceCount) || Number(data.lineCount)">
                                 {{ Number(data.deviceCount || 0) }} / {{ Number(data.lineCount || 0) }}
@@ -40,8 +46,9 @@
 </template>
 
 <script setup lang="ts">
-import { ref } from 'vue'
-import { Refresh } from '@element-plus/icons-vue'
+import { nextTick, ref, watch } from 'vue'
+import type { Component } from 'vue'
+import { Folder, Location, Monitor, OfficeBuilding, Refresh } from '@element-plus/icons-vue'
 import type { TreeInstance } from 'element-plus'
 import type { SteadyDataView } from '@/api/steady/steadyDataView/interface'
 
@@ -49,10 +56,11 @@ defineOptions({
     name: 'SteadyLedgerTree'
 })
 
-defineProps<{
+const props = defineProps<{
     treeData: SteadyDataView.SteadyLedgerNode[]
     loading: boolean
     keyword: string
+    defaultCheckedKeys: string[]
 }>()
 
 const emit = defineEmits<{
@@ -62,6 +70,26 @@ const emit = defineEmits<{
 }>()
 
 const treeRef = ref<TreeInstance>()
+type LedgerLevel = SteadyDataView.SteadyLedgerNode['level']
+const ledgerIcons: Record<LedgerLevel, Component> = {
+    0: OfficeBuilding,
+    1: Folder,
+    2: Monitor,
+    3: Location
+}
+
+const normalizeLedgerLevel = (value: unknown): LedgerLevel => {
+    const level = Number(value)
+    if (level === 0 || level === 1 || level === 2 || level === 3) {
+        return level
+    }
+
+    return 0
+}
+
+const resolveLedgerIcon = (value: unknown) => {
+    return ledgerIcons[normalizeLedgerLevel(value)]
+}
 
 const handleKeywordChange = (value: string) => {
     emit('search', value)
@@ -70,6 +98,19 @@ const handleKeywordChange = (value: string) => {
 const handleCheck = () => {
     emit('change', (treeRef.value?.getCheckedNodes(false, false) || []) as SteadyDataView.SteadyLedgerNode[])
 }
+
+const applyDefaultCheckedKeys = async () => {
+    await nextTick()
+    treeRef.value?.setCheckedKeys(props.defaultCheckedKeys, false)
+}
+
+watch(
+    () => [props.treeData, props.defaultCheckedKeys],
+    () => {
+        applyDefaultCheckedKeys()
+    },
+    { immediate: true }
+)
 </script>
 
 <style scoped lang="scss">
@@ -105,6 +146,35 @@ const handleCheck = () => {
     min-width: 0;
 }
 
+.node-main {
+    display: inline-flex;
+    min-width: 0;
+    align-items: center;
+    gap: 6px;
+}
+
+.node-icon {
+    flex: none;
+    font-size: 15px;
+    color: var(--el-text-color-secondary);
+}
+
+.node-icon.is-level-0 {
+    color: var(--el-color-primary);
+}
+
+.node-icon.is-level-1 {
+    color: var(--el-color-success);
+}
+
+.node-icon.is-level-2 {
+    color: var(--el-color-warning);
+}
+
+.node-icon.is-level-3 {
+    color: var(--el-color-info);
+}
+
 .node-name {
     overflow: hidden;
     text-overflow: ellipsis;
diff --git a/frontend/src/views/steady/steadyDataView/components/SteadyTrendToolbar.vue b/frontend/src/views/steady/steadyDataView/components/SteadyTrendToolbar.vue
index 50a155d..c2b3491 100644
--- a/frontend/src/views/steady/steadyDataView/components/SteadyTrendToolbar.vue
+++ b/frontend/src/views/steady/steadyDataView/components/SteadyTrendToolbar.vue
@@ -25,17 +25,6 @@
             </el-select>
         </div>
 
-        <div class="toolbar-field">
-            <span class="toolbar-field__label">粒度：</span>
-            <el-select
-                :model-value="modelValue.bucket"
-                placeholder="选择时间粒度"
-                @update:model-value="updateField('bucket', $event)"
-            >
-                <el-option v-for="item in bucketOptions" :key="item.value" :label="item.label" :value="item.value" />
-            </el-select>
-        </div>
-
         <div class="toolbar-field">
             <span class="toolbar-field__label">数据：</span>
             <el-select
@@ -44,8 +33,8 @@
                 placeholder="选择数据质量"
                 @update:model-value="updateField('qualityFlag', $event)"
             >
-                <el-option label="仅有效数据" :value="1" />
-                <el-option label="仅无效数据" :value="0" />
+                <el-option label="仅有效数据" :value="0" />
+                <el-option label="仅无效数据" :value="1" />
             </el-select>
         </div>
 
@@ -93,13 +82,6 @@ const emit = defineEmits<{
     reset: []
 }>()
 
-const bucketOptions = [
-    { label: '1分钟', value: '1m' },
-    { label: '5分钟', value: '5m' },
-    { label: '10分钟', value: '10m' },
-    { label: '30分钟', value: '30m' },
-    { label: '1小时', value: '1h' }
-]
 const harmonicOrderOptions = Array.from({ length: 49 }, (_item, index) => index + 2)
 const statLabelMap: Record<SteadyDataView.SteadyTrendStatType, string> = {
     AVG: '平均值',
@@ -136,7 +118,7 @@ const handleTimeBaseDateChange = (value: Date) => {
 <style scoped lang="scss">
 .trend-toolbar {
     display: grid;
-    grid-template-columns: minmax(312px, 1.4fr) repeat(3, minmax(178px, 0.8fr)) auto;
+    grid-template-columns: minmax(312px, 1.4fr) repeat(2, minmax(178px, 0.8fr)) auto;
     gap: 10px;
     align-items: center;
     padding: 12px;
diff --git a/frontend/src/views/steady/steadyDataView/components/SteadyTrendWorkbench.vue b/frontend/src/views/steady/steadyDataView/components/SteadyTrendWorkbench.vue
index 814c55f..09f3feb 100644
--- a/frontend/src/views/steady/steadyDataView/components/SteadyTrendWorkbench.vue
+++ b/frontend/src/views/steady/steadyDataView/components/SteadyTrendWorkbench.vue
@@ -6,6 +6,7 @@
                 :tree-data="ledgerTree"
                 :loading="loading.ledger"
                 :keyword="ledgerKeyword"
+                :default-checked-keys="defaultLedgerCheckedKeys"
                 @refresh="emit('refreshLedger')"
                 @search="emit('ledgerSearch', $event)"
                 @change="emit('ledgerChange', $event)"
@@ -30,6 +31,7 @@
                     :selector-reset-key="selectorResetKey"
                     :tree-data="indicatorTree"
                     :loading="loading.indicator"
+                    :default-checked-keys="defaultIndicatorCheckedKeys"
                     @refresh="emit('refreshIndicator')"
                     @change="emit('indicatorChange', $event)"
                 />
@@ -63,6 +65,8 @@ const props = defineProps<{
         trend: boolean
     }
     ledgerKeyword: string
+    defaultLedgerCheckedKeys: string[]
+    defaultIndicatorCheckedKeys: string[]
     indicatorPanelCollapsed: boolean
     selectorResetKey: number
 }>()
diff --git a/frontend/src/views/steady/steadyDataView/contracts/check-selection-contract.mjs b/frontend/src/views/steady/steadyDataView/contracts/check-selection-contract.mjs
index adde39e..61e7e1f 100644
--- a/frontend/src/views/steady/steadyDataView/contracts/check-selection-contract.mjs
+++ b/frontend/src/views/steady/steadyDataView/contracts/check-selection-contract.mjs
@@ -7,6 +7,8 @@ const currentDir = path.dirname(fileURLToPath(import.meta.url))
 const componentDir = path.join(currentDir, '..', 'components')
 
 const read = file => fs.readFileSync(path.join(componentDir, file), 'utf8')
+const pageSource = fs.readFileSync(path.join(currentDir, '..', 'index.vue'), 'utf8')
+const selectionRulesSource = fs.readFileSync(path.join(currentDir, '..', 'utils', 'selectionRules.ts'), 'utf8')
 
 const expectations = [
     [
@@ -18,6 +20,46 @@ const expectations = [
         'indicator tree excludes half-checked parents when collecting checked nodes',
         /getCheckedNodes\(\s*false\s*,\s*false\s*\)/,
         read('SteadyIndicatorTree.vue')
+    ],
+    [
+        'selection rules expose the first selectable ledger resolver',
+        /export const findFirstSelectableLedgerNode/,
+        selectionRulesSource
+    ],
+    [
+        'selection rules expose the first leaf indicator resolver',
+        /export const findFirstLeafIndicator/,
+        selectionRulesSource
+    ],
+    [
+        'steady page applies default selected ledger keys after ledger tree load',
+        /defaultLedgerCheckedKeys\.value\s*=/,
+        pageSource
+    ],
+    [
+        'steady page applies default selected indicator keys after indicator tree load',
+        /defaultIndicatorCheckedKeys\.value\s*=/,
+        pageSource
+    ],
+    [
+        'ledger tree receives default checked keys',
+        /defaultCheckedKeys/,
+        read('SteadyLedgerTree.vue')
+    ],
+    [
+        'ledger tree renders level icons',
+        /<component\s+:is="resolveLedgerIcon\(data\.level\)"/,
+        read('SteadyLedgerTree.vue')
+    ],
+    [
+        'ledger tree resolves icons by ledger level',
+        /const\s+ledgerIcons[\s\S]*0:[\s\S]*1:[\s\S]*2:[\s\S]*3:/,
+        read('SteadyLedgerTree.vue')
+    ],
+    [
+        'indicator tree receives default checked keys',
+        /defaultCheckedKeys/,
+        read('SteadyIndicatorTree.vue')
     ]
 ]
 
diff --git a/frontend/src/views/steady/steadyDataView/contracts/check-trend-contract.mjs b/frontend/src/views/steady/steadyDataView/contracts/check-trend-contract.mjs
index f3775bf..08f1e1b 100644
--- a/frontend/src/views/steady/steadyDataView/contracts/check-trend-contract.mjs
+++ b/frontend/src/views/steady/steadyDataView/contracts/check-trend-contract.mjs
@@ -53,17 +53,21 @@ const expectations = [
     ['components render indicator checkbox tree', /indicator-tree[\s\S]*show-checkbox[\s\S]*@check/],
     ['components reuse LineChart', /<LineChart/],
     ['toolbar uses shared time period search', /TimePeriodSearch/],
-    ['toolbar labels stat bucket quality filters', /toolbar-field__label[\s\S]*统计：[\s\S]*toolbar-field__label[\s\S]*粒度：[\s\S]*toolbar-field__label[\s\S]*数据：/],
+    ['toolbar labels stat quality filters', /toolbar-field__label[\s\S]*统计：[\s\S]*toolbar-field__label[\s\S]*数据：/],
+    ['toolbar does not render bucket selector', /modelValue\.bucket|bucketOptions|粒度：|选择时间粒度/],
     ['toolbar does not render phase selector', /modelValue\.phases|phaseOptions|resolvePhaseLabel/],
-    ['toolbar labels bucket options descriptively', /bucketOptions[\s\S]*1分钟[\s\S]*1小时/],
     ['toolbar labels quality options descriptively', /仅有效数据[\s\S]*仅无效数据/],
+    ['toolbar binds valid quality flag to zero', /<el-option\s+label="仅有效数据"\s+:value="0"\s*\/>/],
+    ['utilities default to valid quality flag zero', /qualityFlag:\s*0/],
     ['utilities collect selected line ids', /export const collectSelectedLineIds/],
     ['utilities validate selection limits', /export const validateTrendSelection[\s\S]*24/],
     ['utilities do not require phase selection', /if\s*\(!phases\.length\)/],
     ['utilities validate harmonic orders', /export const validateHarmonicOrders[\s\S]*6/],
     ['utilities build trend query payload', /export const buildSteadyTrendQueryPayload/],
     ['utilities strip milliseconds from trend query time', /formatSteadyTrendQueryTime[\s\S]*replace\(\s*\/\\\.\[\^.\]\+\$\//],
+    ['utilities do not send bucket in trend query payload', /bucket:\s*formState\.bucket/],
     ['utilities do not send phases in trend query payload', /phases:\s*formState\.phases/],
+    ['trend query params do not include bucket', /interface\s+SteadyTrendQueryParams\s*{[^}]*bucket\??:\s*string/],
     ['trend query params do not include phases', /phases:\s*string\[\]/],
     ['utilities build chart options', /export const buildSteadyTrendChartOptions/]
 ]
@@ -78,7 +82,6 @@ const sourceByExpectation = [
     componentSource,
     componentSource,
     pageSource,
-    pageSource,
     componentSource,
     pageSource,
     apiSource,
@@ -96,6 +99,8 @@ const sourceByExpectation = [
     componentSource,
     componentSource,
     componentSource,
+    componentSource,
+    componentSource,
     utilitySource,
     utilitySource,
     utilitySource,
@@ -103,6 +108,9 @@ const sourceByExpectation = [
     utilitySource,
     utilitySource,
     utilitySource,
+    utilitySource,
+    utilitySource,
+    interfaceSource,
     interfaceSource,
     utilitySource
 ]
diff --git a/frontend/src/views/steady/steadyDataView/index.vue b/frontend/src/views/steady/steadyDataView/index.vue
index f32715d..1f75073 100644
--- a/frontend/src/views/steady/steadyDataView/index.vue
+++ b/frontend/src/views/steady/steadyDataView/index.vue
@@ -10,6 +10,8 @@
             :show-harmonic-orders="showHarmonicOrders"
             :loading="loading"
             :ledger-keyword="ledgerKeyword"
+            :default-ledger-checked-keys="defaultLedgerCheckedKeys"
+            :default-indicator-checked-keys="defaultIndicatorCheckedKeys"
             :selector-reset-key="selectorResetKey"
             @refresh-ledger="loadLedgerTree"
             @ledger-search="handleLedgerSearch"
@@ -30,6 +32,8 @@ import type { SteadyDataView } from '@/api/steady/steadyDataView/interface'
 import SteadyTrendWorkbench from './components/SteadyTrendWorkbench.vue'
 import {
     collectSelectedLineIds,
+    findFirstLeafIndicator,
+    findFirstSelectableLedgerNode,
     hasHarmonicIndicator,
     resolveAvailableStats,
     validateTrendSelection
@@ -49,6 +53,8 @@ const trendForm = ref(defaultTrendFormState())
 const ledgerKeyword = ref('')
 const indicatorPanelCollapsed = ref(false)
 const selectorResetKey = ref(0)
+const defaultLedgerCheckedKeys = ref<string[]>([])
+const defaultIndicatorCheckedKeys = ref<string[]>([])
 const loading = reactive({
     ledger: false,
     indicator: false,
@@ -75,6 +81,10 @@ const loadLedgerTree = async (keyword = ledgerKeyword.value) => {
     try {
         const response = await getSteadyTrendLedgerTree(keyword ? { keyword } : undefined)
         ledgerTree.value = unwrapData(response) || []
+        const firstLedgerNode = findFirstSelectableLedgerNode(ledgerTree.value)
+        // 台账树首次加载后默认选中第一个可查询监测点，避免趋势查询初始状态为空。
+        selectedLedgerNodes.value = firstLedgerNode ? [firstLedgerNode] : []
+        defaultLedgerCheckedKeys.value = firstLedgerNode ? [firstLedgerNode.id] : []
     } finally {
         loading.ledger = false
     }
@@ -85,6 +95,11 @@ const loadIndicatorTree = async () => {
     try {
         const response = await getSteadyTrendIndicatorTree()
         indicatorTree.value = unwrapData(response) || []
+        const firstIndicator = findFirstLeafIndicator(indicatorTree.value)
+        const firstIndicatorKey = firstIndicator?.id || firstIndicator?.indicatorCode
+        // 指标树首次加载后默认选中第一个叶子指标，并同步驱动统计类型默认值。
+        selectedIndicators.value = firstIndicator ? [firstIndicator] : []
+        defaultIndicatorCheckedKeys.value = firstIndicatorKey ? [firstIndicatorKey] : []
     } finally {
         loading.indicator = false
     }
@@ -109,6 +124,8 @@ const resetTrendState = () => {
     trendForm.value = defaultTrendFormState()
     selectedLedgerNodes.value = []
     selectedIndicators.value = []
+    defaultLedgerCheckedKeys.value = []
+    defaultIndicatorCheckedKeys.value = []
     trendResult.value = null
     selectorResetKey.value += 1
 }
diff --git a/frontend/src/views/steady/steadyDataView/utils/selectionRules.ts b/frontend/src/views/steady/steadyDataView/utils/selectionRules.ts
index 49c7cce..b6478c6 100644
--- a/frontend/src/views/steady/steadyDataView/utils/selectionRules.ts
+++ b/frontend/src/views/steady/steadyDataView/utils/selectionRules.ts
@@ -38,6 +38,39 @@ export const collectLeafIndicators = (nodes: SteadyDataView.SteadyIndicatorNode[
     return indicators
 }
 
+export const findFirstSelectableLedgerNode = (
+    nodes: SteadyDataView.SteadyLedgerNode[]
+): SteadyDataView.SteadyLedgerNode | null => {
+    for (const node of nodes) {
+        if (node.level === 3 || node.selectable) {
+            return node
+        }
+
+        const childNode = findFirstSelectableLedgerNode(node.children || [])
+        if (childNode) return childNode
+    }
+
+    return null
+}
+
+export const findFirstLeafIndicator = (
+    nodes: SteadyDataView.SteadyIndicatorNode[]
+): SteadyDataView.SteadyIndicatorNode | null => {
+    for (const node of nodes) {
+        if (node.children?.length) {
+            const childNode = findFirstLeafIndicator(node.children)
+            if (childNode) return childNode
+            continue
+        }
+
+        if (node.indicatorCode) {
+            return node
+        }
+    }
+
+    return null
+}
+
 export const hasHarmonicIndicator = (indicators: SteadyDataView.SteadyIndicatorNode[]) => {
     return indicators.some(item => item.harmonic || Boolean(item.harmonicOrderStart || item.harmonicOrderEnd))
 }
diff --git a/frontend/src/views/steady/steadyDataView/utils/trendPayload.ts b/frontend/src/views/steady/steadyDataView/utils/trendPayload.ts
index 0bf7c60..b4f22c9 100644
--- a/frontend/src/views/steady/steadyDataView/utils/trendPayload.ts
+++ b/frontend/src/views/steady/steadyDataView/utils/trendPayload.ts
@@ -6,7 +6,6 @@ export interface SteadyTrendFormState {
     timeUnit: TimePeriodUnit
     timeBaseDate: Date
     statTypes: SteadyDataView.SteadyTrendStatType[]
-    bucket: string
     qualityFlag?: number
     harmonicOrders: number[]
 }
@@ -19,8 +18,7 @@ export const defaultTrendFormState = (): SteadyTrendFormState => {
         timeUnit: 'month',
         timeBaseDate: baseDate,
         statTypes: ['AVG'],
-        bucket: '10m',
-        qualityFlag: 1,
+        qualityFlag: 0,
         harmonicOrders: []
     }
 }
@@ -41,7 +39,6 @@ export const buildSteadyTrendQueryPayload = (
         statTypes: formState.statTypes,
         timeStart: formatSteadyTrendQueryTime(formState.timeRange[0] || ''),
         timeEnd: formatSteadyTrendQueryTime(formState.timeRange[1] || ''),
-        bucket: formState.bucket,
         qualityFlag: formState.qualityFlag,
         harmonicOrders: formState.harmonicOrders.length ? formState.harmonicOrders : undefined
     }