diff --git a/.github/workflows/python.yml b/.github/workflows/python.yml
index c6781a4b149..59b14dc3287 100644
--- a/.github/workflows/python.yml
+++ b/.github/workflows/python.yml
@@ -140,12 +140,6 @@ jobs:
       - name: Fetch Submodules and Tags
         shell: bash
         run: ci/scripts/util_checkout.sh
-      - name: Show available RAM size
-        shell: bash
-        run: |
-          hwmemsize=$(sysctl -n hw.memsize)
-          ramsize=$(expr $hwmemsize / $((1024**3)))
-          echo "System Memory: ${ramsize} GB"
       - name: Install Dependencies
         shell: bash
         run: |
diff --git a/ci/appveyor-cpp-setup.bat b/ci/appveyor-cpp-setup.bat
index 261b1183f5b..4f790f05f00 100644
--- a/ci/appveyor-cpp-setup.bat
+++ b/ci/appveyor-cpp-setup.bat
@@ -50,16 +50,16 @@ set CONDA_PACKAGES=
 
 if "%ARROW_BUILD_GANDIVA%" == "ON" (
   @rem Install llvmdev in the toolchain if building gandiva.dll
-  set CONDA_PACKAGES=%CONDA_PACKAGES% --file=ci\conda_env_gandiva_win.yml
+  set CONDA_PACKAGES=%CONDA_PACKAGES% --file=ci\conda_env_gandiva_win.txt
 )
 if "%JOB%" == "Toolchain" (
   @rem Install pre-built "toolchain" packages for faster builds
-  set CONDA_PACKAGES=%CONDA_PACKAGES% --file=ci\conda_env_cpp.yml
+  set CONDA_PACKAGES=%CONDA_PACKAGES% --file=ci\conda_env_cpp.txt
 )
 if "%JOB%" NEQ "Build_Debug" (
   @rem Arrow conda environment is only required for the Build and Toolchain jobs
   conda create -n arrow -q -y -c conda-forge ^
-    --file=ci\conda_env_python.yml ^
+    --file=ci\conda_env_python.txt ^
     %CONDA_PACKAGES%  ^
     "cmake=3.17" ^
     "ninja" ^
diff --git a/ci/conda_env_archery.yml b/ci/conda_env_archery.txt
similarity index 100%
rename from ci/conda_env_archery.yml
rename to ci/conda_env_archery.txt
diff --git a/ci/conda_env_cpp.yml b/ci/conda_env_cpp.txt
similarity index 93%
rename from ci/conda_env_cpp.yml
rename to ci/conda_env_cpp.txt
index 1a8ae6d7edc..def40deb98a 100644
--- a/ci/conda_env_cpp.yml
+++ b/ci/conda_env_cpp.txt
@@ -15,6 +15,7 @@
 # specific language governing permissions and limitations
 # under the License.
 
+# workaround for https://issues.apache.org/jira/browse/ARROW-13134
 aws-sdk-cpp<1.9
 benchmark=1.5.2
 boost-cpp>=1.68.0
diff --git a/ci/conda_env_gandiva.yml b/ci/conda_env_gandiva.txt
similarity index 100%
rename from ci/conda_env_gandiva.yml
rename to ci/conda_env_gandiva.txt
diff --git a/ci/conda_env_gandiva_win.yml b/ci/conda_env_gandiva_win.txt
similarity index 100%
rename from ci/conda_env_gandiva_win.yml
rename to ci/conda_env_gandiva_win.txt
diff --git a/ci/conda_env_python.yml b/ci/conda_env_python.txt
similarity index 100%
rename from ci/conda_env_python.yml
rename to ci/conda_env_python.txt
diff --git a/ci/conda_env_r.yml b/ci/conda_env_r.txt
similarity index 100%
rename from ci/conda_env_r.yml
rename to ci/conda_env_r.txt
diff --git a/ci/conda_env_sphinx.yml b/ci/conda_env_sphinx.txt
similarity index 100%
rename from ci/conda_env_sphinx.yml
rename to ci/conda_env_sphinx.txt
diff --git a/ci/conda_env_unix.yml b/ci/conda_env_unix.txt
similarity index 100%
rename from ci/conda_env_unix.yml
rename to ci/conda_env_unix.txt
diff --git a/ci/docker/conda-cpp.dockerfile b/ci/docker/conda-cpp.dockerfile
index 660ad821655..ff31930c06c 100644
--- a/ci/docker/conda-cpp.dockerfile
+++ b/ci/docker/conda-cpp.dockerfile
@@ -20,12 +20,12 @@ ARG arch
 FROM ${repo}:${arch}-conda
 
 # install the required conda packages into the test environment
-COPY ci/conda_env_cpp.yml \
-     ci/conda_env_gandiva.yml \
+COPY ci/conda_env_cpp.txt \
+     ci/conda_env_gandiva.txt \
      /arrow/ci/
 RUN conda install \
-        --file arrow/ci/conda_env_cpp.yml \
-        --file arrow/ci/conda_env_gandiva.yml \
+        --file arrow/ci/conda_env_cpp.txt \
+        --file arrow/ci/conda_env_gandiva.txt \
         compilers \
         doxygen \
         valgrind && \
diff --git a/ci/docker/conda-integration.dockerfile b/ci/docker/conda-integration.dockerfile
index 1f2c9ac5da2..8a7dd48b947 100644
--- a/ci/docker/conda-integration.dockerfile
+++ b/ci/docker/conda-integration.dockerfile
@@ -26,10 +26,9 @@ ARG jdk=8
 ARG go=1.15
 
 # Install Archery and integration dependencies
-COPY ci/conda_env_archery.yml /arrow/ci/
+COPY ci/conda_env_archery.txt /arrow/ci/
 RUN conda install -q \
-        --file arrow/ci/conda_env_cpp.yml \
-        --file arrow/ci/conda_env_archery.yml \
+        --file arrow/ci/conda_env_archery.txt \
         numpy \
         compilers \
         maven=${maven} \
diff --git a/ci/docker/conda-python.dockerfile b/ci/docker/conda-python.dockerfile
index a7e76974825..ab3f77be1b6 100644
--- a/ci/docker/conda-python.dockerfile
+++ b/ci/docker/conda-python.dockerfile
@@ -21,9 +21,9 @@ FROM ${repo}:${arch}-conda-cpp
 
 # install python specific packages
 ARG python=3.6
-COPY ci/conda_env_python.yml /arrow/ci/
+COPY ci/conda_env_python.txt /arrow/ci/
 RUN conda install -q \
-        --file arrow/ci/conda_env_python.yml \
+        --file arrow/ci/conda_env_python.txt \
         $([ "$python" == "3.6" -o "$python" == "3.7" ] && echo "pickle5") \
         python=${python} \
         nomkl && \
diff --git a/ci/docker/conda.dockerfile b/ci/docker/conda.dockerfile
index 3ea393d3fa9..2e773b5437e 100644
--- a/ci/docker/conda.dockerfile
+++ b/ci/docker/conda.dockerfile
@@ -38,8 +38,8 @@ RUN /arrow/ci/scripts/install_conda.sh ${arch} linux latest ${prefix}
 RUN /arrow/ci/scripts/install_minio.sh ${arch} linux latest ${prefix}
 
 # create a conda environment
-ADD ci/conda_env_unix.yml /arrow/ci/
-RUN conda create -n arrow --file arrow/ci/conda_env_unix.yml git && \
+ADD ci/conda_env_unix.txt /arrow/ci/
+RUN conda create -n arrow --file arrow/ci/conda_env_unix.txt git && \
     conda clean --all
 
 # activate the created environment by default